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                                                                    EXHIBIT 10.9

                       THIRD AMENDMENT TO CREDIT AGREEMENT

     This THIRD AMENDMENT TO CREDIT AGREEMENT (this "Amendment"), made and
entered into as of March 3, 2000, is by and between BUCA, INC., a Minnesota
corporation (the "Borrower"), the banks which are signatories hereto
(individually, a "Bank" and, collectively, the "Banks"), BANK OF AMERICA, N.A.,
a national banking association ("B of A"), as one of the Banks and as co-agent
for the Banks (in such capacity, a "Co-Agent"), FLEET NATIONAL BANK, a national
banking association formerly known as BankBoston, N.A., as one of the Banks and
as co-agent for the Banks (in such capacity, a "Co-Agent") and U.S. BANK
NATIONAL ASSOCIATION, a national banking association, as one of the Banks, and
as agent for the Banks (in such capacity, the "Agent").

                                    RECITALS
                                    --------

     1. U.S. Bank National Association, as Agent and as a Bank, and Bank of
America, N.A., as Co-Agent and as a Bank, and the Borrower entered into a Credit
Agreement dated as of September 27, 1999, as amended by that First Amendment to
Credit Agreement dated as of October 21, 1999, among U.S. Bank National
Association, as Agent and as a Bank, Bank of America, N.A., as Co-Agent and as a
Bank, and BankBoston, N.A., as Co-Agent and as a Bank, and as amended by that
Second Amendment to Credit Agreement dated as of December 24, 1999, among U.S.
Bank National Association, as Agent and as a Bank, Bank of America, N.A., as
Co-Agent and as a Bank, and BankBoston, N.A., as Co-Agent and as a Bank (the
"Credit Agreement"); and

     2. The Borrower has requested that the Banks amend the Credit Agreement in
certain respects.

     3. The parties desire to amend the Credit Agreement, subject to the terms
and conditions set forth in this Amendment.

                                    AGREEMENT
                                    ---------

     NOW, THEREFORE, for good and valuable consideration, the receipt and
adequacy of which are hereby acknowledged, the parties hereto hereby covenant
and agree to be bound as follows:

     Section 1. Capitalized Terms. Capitalized terms used herein and not
otherwise defined herein shall have the meanings assigned to them in the Credit
Agreement, unless the context shall otherwise require.

     Section 2. Amendment. The Credit Agreement is hereby amended as follows:
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          2.1 Definitions

               2.1(a) The definition of "Fixed Charge Coverage Ratio" contained
          in Section 1.1 of the Credit Agreement is hereby amended to read in
          its entirety as follows:

               "Fixed Charge Coverage Ratio": For any date of determination, the
          ratio of

                    (a) the sum of (i) Annualized EBITDA, plus (ii) the product
               of (A) Operating Lease Payments for the immediately preceding
               six-fiscal month period, times (B) two,

                    to

                    (b) the sum (without duplication) of (i) the product of (A)
               Interest Expense for the immediately preceding six-fiscal month
               period, times (B) two, plus (ii) all required principal payments
               with respect to Total Liabilities (including but not limited to
               all such payments with respect to Capitalized Lease Obligations
               of the Borrower and the Subsidiaries) for the immediately
               preceding twelve-fiscal month period, plus (iii) the product of
               (A) Operating Lease Payments for the immediately preceding
               six-fiscal month period, times (B) two, plus (iv) the product of
               (A) $50,000, and (B) the number of restaurants operating as of
               the date of determination, plus (v) the product of (A) income
               taxes of the Borrower and the Subsidiaries accrued for the
               immediately preceding six-fiscal month period, times (B) two,

          in each case determined on a consolidated basis in accordance with
          GAAP.

               2.1(b) The definition of "Revolving (B) Commitment Amount"
          contained in Section 1.1 of the Credit Agreement is hereby amended by
          deleting the reference to "March 26, 2000" therein and replacing it
          with "February 21, 2000", and by deleting the reference to "June 30,
          2000" therein and replacing it with "March 15, 2000."

          2.2 Revolving (B) Commitment. Section 2.1(a) of the Credit Agreement
     is hereby amended by deleting the reference to "June 30, 2000" in clause
     (ii) thereof and replacing it with "March 15, 2000".


                                       -2-
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          2.3 Fixed Charge Coverage Ratio. Section 6.19 of the Credit Agreement
     is hereby amended to read in its entirety as follows:

          Section 6.19 Fixed Charge Coverage Ratio. The Borrower will not permit
     the Fixed Coverage Ratio as of the last day of any quarter which ends
     during any period of measurement described below, to be less than the ratio
     set forth for such period:

                                                       Minimum Fixed
                  Measurement Period               Charge Coverage Ratio
                  ------------------               ---------------------
                  October 1, 1999 through
                      December 31, 1999                1.90 to 1.00

                  January 1, 2000 through
                      March 31, 2000                   1.75 to 1.00

                  Thereafter                           1.60 to 1.00


          2.4 Cash Flow Leverage Ratio. Section 6.20 of the Credit Agreement is
     hereby amended to read in its entirety as follows:

          Section 6.20 Cash Flow Leverage Ratio. The Borrower will not permit
     the Cash Flow Leverage Ratio, as of the last day of any fiscal quarter
     which ends during any period of measurement described below, to be greater
     than the ratio set forth below for such period:

                                                   Maximum Cash Flow
                  Measurement Period                Leverage Ratio
                  ------------------               ------------------
                  October 1, 1999 through
                        March 31, 2000                 3.50 to 1.00

                  April 1, 2000 through
                        June 30, 2000                  3.00 to 1.00

                  Thereafter                           2.75 to 1.00


                                       -3-
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     Section 3. Default and Waiver.

          3.1 Capital Expenditures. Under Section 6.10 of the Credit Agreement,
     the Borrower agreed that it would not, nor would it permit any Subsidiary
     to, make Capital Expenditures, on a consolidated basis, in fiscal year
     1999, in an amount exceeding $31,000,000. The Borrower has advised the
     Agent that its Capital Expenditures for fiscal year 1999 totaled
     approximately $39,200,000. As a result, an Event of Default has occurred
     under Section 7.1(c) of the Credit Agreement. The Borrower has requested
     that the Banks waive such Event of Default.

          3.2 Minimum Fixed Charge Coverage. Under Section 6.19 of the Credit
     Agreement, the Borrower agreed that it would not permit its Fixed Charge
     Covenant Ratio at December 31, 1999 to be less than 1.90:1.00. The Borrower
     has advised the Agent that as at December 31, 1999, the actual Fixed Charge
     Coverage Ratio was 1.31:1.00. As a result, an Event of Default has occurred
     under Section 7.1(c) of the Credit Agreement. The Borrower has requested
     that the Banks waive such Event of Default.

          3.3 Waiver. Upon the date on which the amendments contained in this
     Amendment become effective, the Banks hereby waive the Borrower's Defaults
     and Events of Default described in Section 3.1 and 3.2 hereof. The Borrower
     agrees that the waivers set forth in this Section 3.3 shall be limited to
     the precise meaning of the words as written herein and shall not be deemed
     (a) to be a consent to any waiver or modification of any other term or
     condition of the Credit Agreement or (b) to prejudice any right or remedy
     that the Agent or any Bank may now have or may in the future have under or
     in connection with the Credit Agreement with respect to other Defaults or
     Events of Default. The Borrower acknowledges and agrees that the waivers
     set forth in this Section 3.3 are provided by the Banks as a financial
     accommodation to the Borrower. Except as expressly set forth herein, the
     waivers described in this Section 3.3 shall not alter, affect, release or
     prejudice in any way any of the Borrower's obligations under the Credit
     Agreement. The waivers set forth herein shall not constitute a waiver by
     the Agent or any Bank of any other Default or Event of Default, if any,
     under the Credit Agreement, and shall not be, and shall not be deemed to
     be, a course of action with respect thereto upon which the Borrower may
     rely in the future and the Borrower hereby expressly waives any claim to
     such effect.

     Section 4. Effectiveness of Amendments. The amendments contained in this
Amendment shall become effective upon delivery by the Borrower of, and
compliance by the Borrower with, the following:


                                      -4-
<PAGE>

          4.1 This Amendment, duly executed by the Borrower.

          4.2 A certificate of the Secretary or Assistant Secretary of the
     Borrower (a) certifying as to a copy of the resolutions of the Board of
     Directors of the Borrower authorizing the execution, delivery and
     performance of this Amendment, (b) certifying that there has been no
     amendment to the Articles of Incorporation or Bylaws of the Borrower since
     true and accurate copies of the same were delivered to the Agent with a
     certificate of the Secretary of the Borrower dated September 27, 1999, and
     (c) certifying as to the name, title, and specimen signature of the officer
     or officers of the Borrower authorized to execute this Amendment, and any
     other instrument or agreement executed by the Borrower in connection with
     this Amendment.

          4.3 A certificate of the Chief Financial Officer of the Borrower which
     demonstrates to the Agent's satisfaction that the annualized EBITDA of the
     Borrower was equal to or greater than $5,500,000 as of February 21, 2000.

          4.4 A certificate of the Chief Financial Officer of the Borrower which
     evidences the Borrower's Borrowing Base as of February 21, 2000.

          4.5 Payment of all reasonable unpaid legal fees and other
     out-of-pocket expenses incurred by the Agent through the date of this
     Amendment in connection with this Amendment of which the Borrower has been
     notified as of the date of this Amendment.

          4.6 Payment to Agent of a $15,000 amendment fee.

     Section 5. Representations, Warranties, Authority, No Adverse Claim.

          5.1 Reassertion of Representations and Warranties, No Default. The
     Borrower hereby represents that on and as of the date hereof and after
     giving effect to this Amendment (a) all of the representations and
     warranties contained in the Credit Agreement are true and correct in all
     respects as of the date hereof as though made on and as of such date,
     except for changes permitted by the terms of the Credit Agreement, and (b)
     there will exist no Default or Event of Default under the Credit Agreement
     as amended by this Amendment on such date which has not been waived by the
     Agent.

          5.2 Authority, No Conflict, No Consent Required. The Borrower
     represents and warrants that the Borrower has the corporate power and
     authority to enter into this Amendment and has duly authorized the
     execution and delivery of this


                                      -5-
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     Amendment and any other agreements and documents executed and delivered by
     the Borrower in connection herewith by proper corporate action, and, except
     as set forth in Schedule 4.3 to the Credit Agreement, none of this
     Amendment nor the agreements contained herein contravenes or constitutes a
     default under any agreement, instrument or indenture to which the Borrower
     is a party or a signatory or a provision of the Borrower's Articles of
     Incorporation or Bylaws or any requirement of law presently in effect and
     applicable to the Borrower, or results in the imposition of any Lien on any
     of its property under any agreement binding on or applicable to the
     Borrower or any of its property except, if any, in favor of the Agent and
     except where the contravention or default or the imposition of such Lien
     could not adversely affect the validity or enforceability of this Amendment
     or constitute a Material Adverse Occurrence. The Borrower represents and
     warrants that, except as set forth in Schedule 4.3 to the Credit Agreement,
     no consent, approval or authorization of or registration or declaration
     with any Person, including but not limited to any governmental authority,
     is required on the part of the Borrower in connection with the execution
     and delivery by the Borrower of this Amendment or any other agreements and
     documents executed and delivered by the Borrower in connection herewith or
     the performance of obligations of the Borrower herein described, except for
     those which the Borrower has obtained or provided and as to which the
     Borrower has delivered certified copies of documents evidencing each such
     action to the Agent and except where the failure to obtain such consent,
     approval or authorization or to make such registration or declaration could
     not adversely effect the validity or enforceability of this Amendment or
     constitute a Material Adverse Occurrence.

          5.3 No Adverse Claim. The Borrower warrants, acknowledges and agrees
     that to the Borrower's knowledge no events have been taken place and no
     circumstances exist at the date hereof which would give the Borrower a
     basis to assert a defense, offset or counterclaim to any claim of the Banks
     with respect to the Borrower's obligations under the Credit Agreement as
     amended by this Amendment.

     Section 6. Affirmation of Credit Agreement, Further References, Affirmation
of Security Interest. The Banks and the Borrower each acknowledge and affirm
that the Credit Agreement, as hereby amended, is hereby ratified and confirmed
in all respects and all terms, conditions and provisions of the Credit
Agreement, except as amended by this Amendment, shall remain unmodified and in
full force and effect. All references in any document or instrument to the
Credit Agreement are hereby amended and shall refer to the Credit Agreement as
amended by this Amendment. The Borrower confirms to the Banks that the
Borrower's obligations under the Credit Agreement, as amended by this Amendment,
are and continue to be secured by the security interest


                                      -6-
<PAGE>

granted by the Borrower in favor of the Agent under that certain Security
Agreement (Borrower), that certain Pledge Agreement, and that certain Collateral
Assignment of Trademarks, all dated as of September 27, 1999, and made by the
Borrower in favor of the Agent, and all of the terms, conditions, provisions,
agreements, requirements, promises, obligations, duties, covenants and
representations of the Borrower under such documents and any and all other
documents and agreements entered into with respect to the obligations under the
Credit Agreement are incorporated herein by reference and are hereby ratified
and affirmed in all respects by the Borrower.

     Section 7. Successors. This Amendment shall be binding upon the Borrower
and the Banks and their respective successors and assigns, and shall inure to
the benefit of the Borrower and the Banks and the successors and assigns of the
Banks.

     Section 8. Legal Expenses. As provided in Section 9.2 of the Credit
Agreement, the Borrower agrees to reimburse the Agent, upon execution of this
Amendment, for all reasonable out-of-pocket expenses (including reasonable
attorney' fees and legal expenses of Dorsey & Whitney LLP, counsel for the
Agent) incurred in connection with negotiation, preparation and execution of
this Amendment and all other documents negotiated, prepared and executed in
connection with this Amendment, and in enforcing the obligations of the Borrower
under this Amendment, and to pay and save the Banks harmless from all liability
for any stamp or other taxes which may be payable with respect to the execution
or delivery of this Amendment, which obligations of the Borrower shall survive
any termination of the Credit Agreement.

     Section 9. Counterparts. This Amendment may be executed in several
counterparts as deemed necessary or convenient, each of which, when so executed,
shall be deemed an original, provided that all such counterparts shall be
regarded as one and the same document, and any party to this Amendment may
execute such agreement by executing a counterpart of such agreement.

     Section 10. Governing Law. THIS AMENDMENT SHALL BE GOVERNED BY THE INTERNAL
LAWS OF THE STATE OF MINNESOTA, WITHOUT GIVING EFFECT TO CONFLICT OF LAW
PRINCIPLES THEREOF, BUT GIVING EFFECT TO FEDERAL LAWS APPLICABLE TO NATIONAL
BANKS, THEIR HOLDING COMPANIES AND THEIR AFFILIATES.

     Section 11. Capacity. All agreements and waivers of any of the Banks
hereunder or under any previous amendments to the Credit Agreement shall be
considered to have been made or given by such Bank in both its capacity as a
Bank and its capacity as the Agent or a Co-Agent, as applicable.


                                      -7-
<PAGE>

     IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be
executed as of the date and year first above written.

                                       BUCA, INC.


                                       By: /s/ Greg Gadel
                                           -------------------------------------

                                       Title: Chief Financial Officer
                                              ----------------------------------

                                       Address:
                                       Attention:  Greg A. Gadel
                                       1300 Nicollet Avenue
                                       Suite 5003
                                       Minneapolis, MN  55403

                                       Telephone No.:  (612) 288-2382
                                       Telecopier No.:  (612)  827-6446


                                       S-1
                        Signature page to Third Amendment
<PAGE>

                                       U.S. BANK NATIONAL ASSOCIATION, as
                                       Agent and a Bank

                                       By: /s/ Joshua Pirozzolo
                                           -------------------------------------

                                       Title: Commercial Banking Officer
                                              ----------------------------------
                                       Address:
                                       Attention: Joshua R. Pirozzolo  MPFP0602
                                       601 Second Avenue South
                                       Minneapolis, MN 55402-4302

                                       Telephone No.: (612) 973-0520
                                       Telecopier No.:  (612) 973-0823


                                       S-2
                        Signature page to Third Amendment
<PAGE>

                                       BANK OF AMERICA, N.A., as Co-Agent and
                                       a Bank

                                       By: /s/ William Richards
                                           -------------------------------------

                                       Title: Vice President
                                              ----------------------------------

                                       Address:
                                       Attention:  William S. Richards, Jr.
                                       IL1-231-06-13
                                       231 South LaSalle Street
                                       Chicago, IL 60697

                                       Telephone No.:  (312) 828-2731
                                       Telecopier No.:  (312) 828-1974


                                       S-3
                        Signature page to Third Amendment
<PAGE>

                                       FLEET NATIONAL BANK, as Co-Agent and
                                       a Bank

                                       By: /s/ Christopher Holtz
                                           -------------------------------------

                                       Title:  Division Executive
                                              ----------------------------------

                                       Address:
                                       Attention: Christopher M. Holtz
                                       MAD 10009 E
                                       100 Federal Street
                                       Boston, MA 02110

                                       Telephone No.:  (617) 434-7690
                                       Telecopier No.:  (617) 434-0630


                                       S-4
                        Signature page to Third Amendment