<PAGE>   1



                                                                     EXHIBIT 10


                           AMENDMENT NO. 2 AND CONSENT


                                                Dated as of March 10, 1999

To the banks, financial institutions and other
   institutional lenders (collectively, the "Banks")
   party to the Credit Agreement referred to
   below, to Citibank, N.A., as administrative
   agent (the "Agent") for the Banks, to SunTrust
   Bank, Nashville, N.A., as the swing line bank,
   and to NationsBank, N.A., as documentation agent

Ladies and Gentlemen:

          We refer to the Second Amended and Restated Revolving Credit Agreement
dated as of April 2, 1998, and the Amendment No.1 and Consent thereto dated as
of September 22, 1998 (such Credit Agreement, as so amended, the "Credit
Agreement") among the undersigned and you. Capitalized terms not otherwise
defined in this Amendment No. 2 and Consent have the same meanings as specified
in the Credit Agreement.

          It is hereby agreed by you and us as follows:

          The Credit Agreement is, effective as of the date of this Amendment 
No. 2 and Consent, hereby amended as follows:

          (a) The definition of "EBITDA" in Section 1.01 is amended by adding at
     the end thereof new clauses (xi), (xii) and (xiii) to read as follows:

          "plus (xi) in the case of the fiscal quarters ending December 31, 1998
          and the following three quarters, the aggregate amount of any
          reduction in Net Income attributable to any non-cash charge for the
          revaluation of assets made in accordance with generally accepted
          accounting principles, provided that such reduction shall not exceed
          $110,400,000 (prior to any adjustment for income taxes) plus (xii) in
          the case of the fiscal quarter ending March 31, 1999 and the following
          three quarters, the aggregate amount of any reduction in Net Income
          attributable to any charge for the revaluation of assets made and/or
          any restructuring charges taken, in each case in accordance with
          generally accepted accounting principles, provided that such reduction
          shall not exceed $8,700,000 (prior to any adjustment for income taxes)
          plus (xiii) in the case of the fiscal quarter ending December 31, 1999
          and the following three quarters, the aggregate

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          amount of any reduction in Net Income attributable to any charge
          related to the implementation of SFAS No. 133 made in accordance with
          generally accepted accounting principles, provided that such non-cash
          reduction shall not exceed $10,000,000 (prior to any adjustment for
          income taxes)."

          (b) The definition of "Applicable Eurodollar Rate Margin" in Section
     1.01 is amended by (i) deleting the phrase "0.5000% per annum and
     thereafter 0.6750% per annum" in the first sentence thereof and
     substituting therefor the phrase "0.6750% per annum and thereafter 0.8500%
     per annum", (ii) deleting the date "September 30, 1998" in the second to
     last sentence thereof and substituting therefor the date "March 31, 1999",
     (iii) deleting the figure "0.6750%" in the last sentence thereof and
     substituting therefor the figure "0.8500%" and (iv) deleting the table
     therein and substituting therefor the following table:

<TABLE>
<CAPTION>
                                                            Applicable Eurodollar
                  "Consolidated                                 Rate Margin for
                 Debt/EBITDA Ratio                                 Advances
              ----------------------                         --------------------

     <S>                                                    <C>
     Greater than 3.50 to 1.00                                    0.8500%

     Less than or equal to 3.50 to 1.00 but                       0.6750%
     greater than 3.00 to 1.00
 
     Less than or equal to 3.00 to 1.00 but                       0.5000%
     greater than 2.50 to 1.00
 
     Less than or equal to 2.50 to 1.00 but                       0.4250%
     greater than 2.00 to 1.00

     Less than or equal to 2.00 to 1.00                           0.3250%"
</TABLE>

 
          (c) The definition of "Applicable Facility Fee Rate" in Section 1.01
     is amended by (i) deleting the phrase "0.2500% per annum and thereafter for
     each Effective Period (as defined below) 0.3250% per annum" in the first
     sentence thereof and substituting therefor the phrase "0.3250% per annum
     and thereafter for each Effective Period (as defined below) 0.4000% per
     annum", (ii) deleting the date "September 30, 1998" in the second to last
     sentence thereof and substituting therefor the date "March 31, 1999", (iii)
     deleting the figure "0.3250%" in the last sentence thereof and substituting
     therefor the figure "0.4000%" and (iv) deleting the table therein and
     substituting therefor the following table:

<TABLE>
<CAPTION>
  
                                                         Applicable Facility Fee
                  "Consolidated                                Rate for
                 Debt/EBITDA Ratio                             Advances
               ---------------------                    ------------------------
     <S>                                                <C>
     Greater than 3.50 to 1.00                                 0.4000%


</TABLE>





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<PAGE>   3

<TABLE>
<CAPTION>

                                                         Applicable Facility Fee
                  "Consolidated                                Rate for
                 Debt/EBITDA Ratio                             Advances
               ---------------------                    ------------------------
         <S>                                            <C>
         Less than or equal to 3.50 to 1.00 but                 0.3250%
         greater than 3.00 to 1.00

         Less than or equal to 3.00 to 1.00 but                 0.2500%
         greater than 2.50 to 1.00

         Less than or equal to 2.50 to 1.00 but                 0.2000%
         greater than 2.00 to 1.00

         Less than or equal to 2.00 to 1.00                     0.1750%"
</TABLE>


                  (d) The definition of "Applicable Letter of Credit Fee Rate"
         in Section 1.01 is amended by (i) deleting the phrase "0.3750% per
         annum and thereafter for each Effective Period (as defined below)
         0.5000% per annum" in the first sentence thereof and substituting
         therefor the phrase "0.5500% per annum and thereafter for each
         Effective Period (as defined below) 0.7250% per annum", (ii) deleting
         the date "September 30, 1998" in the second to last sentence thereof
         and substituting therefor the date "March 31, 1999", (iii) deleting the
         figure "0.5000%" in the last sentence thereof and substituting therefor
         the figure "0.7250%" and (iv) deleting the table therein and
         substituting therefor the following table:

<TABLE>
<CAPTION>


                   "Consolidated                         Applicable Letter of Credit
                 Debt/EBITDA Ratio                                Fee Rate
               ---------------------                     ---------------------------
         <S>                                             <C>
         Greater than 3.50 to 1.00                                 0.7250%

         Less than or equal to 3.50 to 1.00 but                    0.5500%
         greater than 3.00 to 1.00
 
         Less than or equal to 3.00 to 1.00 but                    0.3750%
         greater than 2.50 to 1.00

         Less than or equal to 2.50 to 1.00 but                    0.3000%
         greater than 2.00 to 1.00
 
         Less than or equal to 2.00 to 1.00                        0.2000%"

</TABLE>

                  (e) The definition of "Applicable Utilization Fee Rate" in
         Section 1.01 is amended by (i) deleting the phrase "0.1250% per annum"
         in the first sentence thereof and substituting therefor the phrase
         "0.2500% per annum", (ii) deleting the date "September 30, 1998" in the
         second to last sentence thereof and substituting therefor the date
         "March 31, 1999" and (iii) deleting the table therein and substituting
         therefor the following table:




 
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<PAGE>   4

<TABLE>
<CAPTION>

                                                        Applicable Utilization Fee
                      "Consolidated                            Rate for
                    Debt/EBITDA Ratio                          Advances
                 ----------------------                   ---------------------
         <S>                                             <C>
         Greater than 3.50 to 1.00                               0.2500%

         Less than or equal to 3.50 to 1.00 but                  0.2500%
         greater than 3.00 to 1.00

         Less than or equal to 3.00 to 1.00 but                  0.1250%
         greater than 2.50 to 1.00

         Less than or equal to 2.50 to 1.00 but                  0.1250%
         greater than 2.00 to 1.00
 
         Less than or equal to 2.00 to 1.00                      0.1250%"
 
</TABLE>

                  (f) The definition of "Fixed Charge Coverage Ratio" in Section
         1.01 is amended by adding at the end thereof the following:

                      "plus, in the case of the quarter ended September 30, 
                      2002, the current portion of the notional amount of the 
                      4.5% Convertible Subordinated Debentures, due 2003, and 
                      the current portion of the public Subordinated Debt to
                      refinance the 4.5% Convertible Subordinated Debentures,
                      due 2003."

                  (g) The definition of "Guarantors" in Section 1.01 is amended
         by deleting the second proviso therein and replacing such proviso with
         the following proviso:

                      "; and provided further that the Subsidiaries listed on
                                              Schedule VIII hereto shall not be
                                              Guarantors so long as less than 
                                              9.0% of the EBITDA of the Borrower
                                              and its Subsidiaries (calculated 
                                              on a rolling four quarter basis)
                                              is attributable to their interests
                                              in such Subsidiaries."

                  (h) Section 3.01 is amended by deleting the figure
         "$25,000,000" in the fifth line thereof and substituting therefor the
         figure "$50,000,000".

                  (i) Section 6.01(j) is amended by (i) adding to the end of
         clause (C) thereof the following proviso:





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<PAGE>   5

                    ", provided that the Subsidiaries listed on Schedule VIII
                    hereto shall not enter into the Intercompany Subordination
                    Agreement so long as less than 9.0% of the EBITDA of the
                    Borrower and its Subsidiaries (calculated on a rolling four
                    quarter basis) is attributable to their interests in such
                    Subsidiaries"

       and (ii) adding to the end of such Section a new clause (E), to read as
    follows:


                    "(E) If, at any time, the Borrower's Debt is rated at or
                    below BB- by Standard & Poor's Ratings Group or Ba3 by
                    Moody's Investors Service, Inc., then the Borrower shall
                    promptly and in any event within ten Business Days (or, in
                    the case of any Subsidiary referred to below, such other
                    time period as agreed by the Agent) after the announcement
                    of such downgrade (i) pledge and deliver to the Agent as
                    security for its benefit and the ratable benefit of the
                    Banks all of the Securities (accompanied by undated stock
                    powers executed in blank) of each of its Subsidiaries that
                    is not (x) an Immaterial Subsidiary or (y) listed on
                    Schedule VIII, (ii) execute and deliver a pledge agreement
                    in form and substance reasonably satisfactory to the Agent,
                    (iii) take all such other action as the Agent may deem
                    necessary or desirable in order to obtain and maintain, from
                    and after the time such Securities are pledged and delivered
                    to the Agent, a perfected, first priority lien on and
                    security interest in such Securities (and all dividends,
                    cash, instruments and other property from time to time
                    received, receivable or otherwise distributed in respect of
                    or in exchange for any or all of such Securities), and (iv)
                    use all reasonable efforts to pledge and deliver to the
                    Agent as security for its benefit and the ratable benefit of
                    the Banks all of the Securities (accompanied by undated
                    stock powers executed in blank) of each of the Subsidiaries
                    described in clause (i)(y) as soon as practicable following
                    the date of such downgrade so long as such pledge and
                    delivery would not adversely affect the business of such
                    Subsidiary."

                (j) Section 6.02(e)(i) is amended by deleting the figure
    "$75,000,000" in clause (C) thereof and replacing such figure with the
    following phrase:

                    "(1) $15,000,000 if, at the time of such Common Stock
                    Payment, the Borrower's Consolidated Debt/EBITDA Ratio is
                    greater than or equal to 3.50 to 1.00, (2) $25,000,000 if,
                    at the time of such Common Stock Payment, the Borrower's
                    Consolidated Debt/EBITDA Ratio is less than 3.50 to 1.00 but
                    greater than or equal to 3.00 to 1.00, or (3) $50,000,000
                    if, at the time of such Common Stock Payment, the Borrower's
                    Consolidated Debt/EBITDA Ratio is less than 3.00 to 1.00".

                (k) Section 6.02(f)(i) is amended by (i) deleting in clause
    (A) thereof the figure "$75,000,000" and substituting therefor the figure
    "25,000,000" and (ii) deleting in clause



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<PAGE>   6

      (B) thereof the phrase "shall not exceed $500,000,000" and substituting 
      therefor the phrase "(commencing on and after the date of Amendment No. 2
      and Consent to this Agreement) shall not exceed $150,000,000".

                (l) Section 6.02(f)(ii) is amended by deleting the figure
      "$75,000,000" in the fifth line thereof and substituting therefor the
      figure "25,000,000".

                (m) Section 6.02(f)(viii) is amended by deleting the figure
      "$75,000,000" therein and replacing such figure with the following phrase:

                    "(1) $15,000,000 if, at the time of such Capital Investment,
                    the Borrower's Consolidated Debt/EBITDA Ratio is greater
                    than or equal to 3.50 to 1.00, (2) $25,000,000 if, at the
                    time of such Capital Investment, the Borrower's Consolidated
                    Debt/EBITDA Ratio is less than 3.50 to 1.00 but greater than
                    or equal to 3.00 to 1.00, or (3) $50,000,000 if, at the time
                    of such Capital Investment, the Borrower's Consolidated
                    Debt/EBITDA Ratio is less than 3.00 to 1.00".

                (n) Section 6.02(j)(vii) is amended by deleting the figure
       "$75,000,000" therein and replacing such figure with the following
       phrase:

                    "(1) $15,000,000 if, at the time of such purchase, the 
                    Borrower's Consolidated Debt/EBITDA Ratio is greater than or
                    equal to 3.50 to 1.00, (2) $25,000,000 if, at the time of
                    such purchase, the Borrower's Consolidated Debt/EBITDA Ratio
                    is less than 3.50 to 1.00 but greater than or equal to 3.00
                    to 1.00, or (3) $50,000,000 if, at the time of such
                    purchase, the Borrower's Consolidated Debt/EBITDA Ratio is
                    less than 3.00 to 1.00".

                (o) Section 6.02 is amended by adding at the end thereof a new 
       subsection (p) to read as follows:

                    "(p) Transfers to Excluded Subsidiaries. Sell, lease,
                    transfer or otherwise dispose of any of its assets
                    (including cash), or permit any Guarantor to sell, lease,
                    transfer or otherwise dispose of any of its assets
                    (including cash), to any of the Subsidiaries listed on
                    Schedule VIII such that, immediately after giving effect to
                    such sale, lease, transfer or other disposition, the
                    aggregate value of the assets of the Subsidiaries listed on
                    Schedule VIII shall be greater than 9.0% of the aggregate
                    value of the assets of the Borrower and its Subsidiaries."

                (p) Section 6.03(b) is amended by (i) inserting after the
       phrase "for each such period" therein the parenthetical "(other than
       the period ending September 30, 2002)" and (ii) adding at the end thereof
       the phrase ", and for the period ending September 30, 2002, 3.50 
       to 1.00."




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<PAGE>   7

                  (q) The Credit Agreement is amended by adding Schedule VIII
         thereto to read as set forth on Schedule I hereto.

                  Notwithstanding the provisions of Section 7.01(j), the
Majority Banks hereby consent to the termination of the Service Agreements
listed on Schedule II hereto.

                  This Amendment No. 2 and Consent shall become effective as of
the date first above written when, and only when, (i) the Agent shall have
received counterparts of this Amendment No. 2 and Consent executed by the
undersigned, the Issuing Bank and the Majority Banks or, as to any of the Banks,
advice satisfactory to the Agent that such Bank has executed this Amendment No.
2 and Consent, (ii) the Agent shall have received, for the ratable account of
each Bank approving this Amendment No. 2 and Consent on or prior to 5:00 p.m.
(New York City time) on March 12, 1999, a consent fee of 1/8 of one percent of
each such Bank's Commitment, and (iii) the consent attached hereto executed by
each Guarantor. This Amendment No. 2 and Consent is subject to the provisions of
Section 9.01 of the Credit Agreement.

                  On and after the effectiveness of this Amendment No. 2 and
Consent, each reference in the Credit Agreement to "this Agreement",
"hereunder", "hereof" or words of like import referring to the Credit Agreement,
and each reference in the Notes and each of the other Loan Documents to "the
Credit Agreement", "thereunder", "thereof" or words of like import referring to
the Credit Agreement, shall mean and be a reference to the Credit Agreement, as
amended by this Amendment No. 2 and Consent.

                  The Credit Agreement, the Notes and each of the other Loan
Documents, as specifically amended by this Amendment No. 2 and Consent, are and
shall continue to be in full force and effect and are hereby in all respects
ratified and confirmed. The execution, delivery and effectiveness of this
Amendment No. 2 and Consent shall not, except as expressly provided herein,
operate as a waiver of any right, power or remedy of any Bank or the Agent under
any of the Loan Documents, nor constitute a waiver of any provision of any of
the Loan Documents.

                  If you agree to the terms and provisions hereof, please
evidence such agreement by executing and returning at least three counterparts
of this Amendment No. 2 and Consent to Michael Stein at Shearman & Sterling, 599
Lexington Avenue, New York, NY 10022 (Telecopier No. (212) 848-7179).

                  This Amendment No. 2 and Consent may be executed in any number
of counterparts and by different parties hereto in separate counterparts, each
of which when so executed shall be deemed to be an original and all of which
taken together shall constitute one and the same agreement. Delivery of an
executed counterpart of a signature page to this Amendment No. 2 and Consent by
telecopier shall be effective as delivery of a manually executed counterpart of
this Amendment No. 2 and Consent.

                  This Amendment No. 2 and Consent shall be governed by, and 
construed in accordance with, the laws of the State of New York.




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<PAGE>   8


                                       Very truly yours,

                                       PHYCOR, INC.



                                       By /s/ John K. Crawford 
                                          --------------------------------
                                          Title: Executive Vice President
                                                 and Chief Financial Officer








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<PAGE>   9





Agreed as of the date first above written:

CITIBANK, N.A.,
      as Agent, as an Issuing Bank and as Bank



By /s/ Gregory K. Park
  ---------------------------------------
  Title: Vice President



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<PAGE>   10


NATIONSBANK, N.A.
     as Documentation Agent



By Kevin Wagley
  ---------------------------------------
  Title: Vice President




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<PAGE>   11




BANK OF AMERICA NT & SA




By Kevin Wagley
  ---------------------------------------
  Title: Vice President



                                       11









<PAGE>   12






BANKERS TRUST COMPANY




By David J. Bell
  ---------------------------------------
  Title: Principal




                                       12











<PAGE>   13




CREDIT LYONNAIS NEW YORK BRANCH




By Henry Reukauf
  ---------------------------------------      
  Title: Vice President




                                       13









<PAGE>   14







FIRST AMERICAN NATIONAL BANK




By Allison H. Jones 
  ---------------------------------------
  Title: Senior Vice President



                                       14








<PAGE>   15




THE FIRST NATIONAL BANK OF CHICACO




By /s/ First National Bank of Chicago
  ---------------------------------------
  Title: 




                                       15








<PAGE>   16





FIRST UNION NATIONAL BANK




By /s/ Carolyn Hannon
  ---------------------------------------
  Title: Director



                                       16








<PAGE>   17






MELLON BANK, N.A.




By /s/ Scott Hennessee 
  ---------------------------------------
  Title: Vice President



                                       17








<PAGE>   18




COOPERATIEVE CENTRALE RAIFFEISEN
BOERENLEENBANK B.A., "RABOBANK NEDERLAND",
NEW YORK BRANCH




By Terrell Boyle
  ---------------------------------------
  Title: Vice President

By Jeff Vollack
  ---------------------------------------





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<PAGE>   19







THE SUMITOMO BANK, LIMITED




By Gary Franke
  --------------------------------------- 
  Title: Vice President and Manager





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