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                                                                   EXHIBIT 10.17
                            MAVERICK TUBE CORPORATION

                   FIRST AMENDMENT TO SECURED CREDIT AGREEMENT



Harris Trust and Savings Bank
Chicago, Illinois
Mercantile Bank National Association
St. Louis, Missouri
Ladies and Gentlemen:

Reference is hereby made to that certain  Secured Credit  Agreement  dated as of
September 18, 1998 (the "Credit Agreement") among the undersigned, Maverick Tube
Corporation,  a Delaware  corporation  (the  "Borrower"),  you (the "Banks") and
Harris Trust and Savings Bank, as agent for the Banks (the "Agent"). All defined
terms used herein shall have the same meaning as in the Credit  Agreement unless
otherwise defined herein.

The  Borrower,  the Agent and the Banks  wish to amend the  definition  of Fixed
Charge  Coverage  Ratio and to modify  certain other terms and conditions of the
Credit Agreement, all on the terms and conditions set forth in this Amendment.

Section 1.        Amendments to Credit Agreement.
Upon  satisfaction  of all of the  conditions  precedent  set forth in Section 2
hereof, the Credit Agreement shall be amended as follows:

         1.1.  Section  4.1 of the Credit  Agreement  shall be amended by adding
thereto the following definitions:

         "Consolidated  Net Income  Available for Fixed Charges" shall mean, for
         any period,  earnings before interest and taxes plus  depreciation  and
         amortization  plus operating  lease expenses less capital  expenditures
         (excluding,  in any event, (i) any  expenditures  arising from the PMAC
         Acquisition to the extent and only to the extent such expenditures were
         contemplated by the terms of the Acquisition Documents and (ii) capital
         expenditures  incurred in connection with the PMAC  Acquisition  during
         the  Borrower's  Fiscal  Year  1999  in an  amount  not  in  excess  of
         $5,600,000)  plus, for the Borrower's  fiscal quarters ending September
         30, 1998, December 31, 1998, March 31, 1999 and June 30, 1999, software
         and  development  related  charges  incurred  during the fourth  fiscal
         quarter of the  Borrower's  Fiscal Year 1998 in an amount not in excess
         of $1,600,000,  all determined on a consolidated basis for the Borrower
         and its Subsidiaries in accordance with generally  accepted  accounting
         principles, consistently applied.

         "Fixed  Charges"  shall mean,  for any period,  interest  expense  plus
         operating lease expenses and all principal  payments under  Capitalized
         Leases  plus  current  scheduled  maturities  of all  indebtedness  for
         borrowed money other than the Revolving Credit Loans, all determined on
         a  consolidated   basis  for  the  Borrower  and  its  Subsidiaries  in
         accordance with generally accepted accounting principles,  consistently
         applied.

         1.2. The  definition  of "Fixed  Charge  Coverage  Ratio"  appearing in
Section  4.1 of the Credit  Agreement  shall be amended in its  entirety  and so
amended shall be restated to read as follows:

         "Fixed Charge Coverage Ratio" shall mean, at any time the same is to be
         determined,  the ratio of (a)  Consolidated  Net Income  Available  for
         Fixed Charges,  for the four most recently completed fiscal quarters of
         the Borrower,  to (b) Fixed Charges,  for the same four fiscal quarters
         of the Borrower.

         1.3.  Section  7.12 of the  Credit  Agreement  shall be  amended in its
entirety and as amended shall be restated to read as follows:

         Minimum Fixed Charge Coverage Ratio.  The Borrower,  as of the close of
         any fiscal  quarter of the  Borrower,  will not permit its Fixed Charge
         Coverage  ratio to be less than (i) 1.0 to 1 for each of the Borrower's
         fiscal quarters ended September 30, 1998,  December 31, 1998, March 31,
         1999 and June 30, 1999,  and (ii) 1.25 to 1 for each fiscal  quarter of
         the Borrower thereafter.

         1.4.  Schedule I to the Compliance  Certificate of the Credit Agreement
shall be amended in its entirety and as so amended  shall be restated to read as
set forth on Exhibit A hereto.

Section 2.        Conditions Precedent.

The effectiveness of this Amendment is subject to the satisfaction of all of the
following conditions precedent:

         2.1. The  Borrower,  the Agent and the Banks shall have  executed  this
Amendment (such execution may be in several counterparts and the several parties
hereto may execute on separate counterparts).

         2.2. A Guarantor's Consent for the benefit of the Banks shall have been
executed and delivered to the Agent, a form of which is attached hereto.

         2.3. The Borrower shall be in full compliance with all of the terms and
conditions of the Loan  Documents  and no Event of Default or Potential  Default
shall have  occurred and be  continuing  thereunder or shall result after giving
effect to this Amendment.

         2.4.  Legal  matters  incident to the  execution  and  delivery of this
Amendment shall be satisfactory to each of the Banks and their legal counsel.

         2.5.  The Agent  shall  have  received  payment by the  Borrower  of an
amendment fee in the amount of $5,000 for the ratable benefit of the Banks.

Section 3.        Representations And Warranties.

The Borrower, by its execution of this Amendment, hereby certifies and  warrants
the following:

         (a) each of the representations and warranties set forth  in  Section 5
of the Credit  Agreement is true and correct as of the date hereof as if made on
the date  hereof,  except that the  representations  and  warranties  made under
Section 5.2 shall be deemed to refer to the most recent annual report  furnished
to the Banks by the Borrower; and

         (b) the  Borrower  is in full  compliance  with  all of the  terms  and
conditions of the Credit Agreement and no Event of Default or Potential  Default
has occurred and is continuing thereunder.


Section 4.        Miscellaneous.

         4.1. The Borrower has  heretofore  executed and  delivered to the Agent
the Security Agreement and the Borrower hereby agrees that  notwithstanding  the
execution and delivery  hereof,  such Security  Agreement shall be and remain in
full force and effect and that any rights and remedies of the Agent  thereunder,
obligations  of the  Borrower  thereunder  and any liens or  security  interests
created or provided for thereunder shall be and remain in full force and effect,
shall not be affected,  impaired or  discharged  thereby and shall secure all of
its  indebtedness,  obligations and liabilities to the Agent and the Banks under
the Credit  Agreement as amended hereby.  Nothing herein  contained shall in any
manner affect or impair the priority of the liens and security interests created
and provided for by the Security Agreement as to the indebtedness which would be
secured thereby prior to giving effect hereto.
         4.2. Reference to this specific Amendment need not be made in any note,
document,  letter,  certificate,  any security  agreement,  or any communication
issued  or made  pursuant  to or  with  respect  to the  Credit  Agreement,  any
reference  to the  Credit  Agreement  being  sufficient  to refer to the  Credit
Agreement as amended hereby.
         4.3. This Amendment may be executed in any number of counterparts,  and
by the different parties on different counterparts,  all of which taken together
shall  constitute  one and the same  agreement.  Any of the  parties  hereby may
execute  this  agreement  by  signing  any  such  counterpart  and  each of such
counterparts shall for all purposes be deemed to be an original.  This agreement
shall be governed by the internal laws of the State of Illinois.
         4.4.  The Borrower  agrees to pay all  reasonable  costs and  expenses,
including without limitation  attorneys fees,  incurred by the Agent and each of
the  Banks  in  connection  with the  preparation,  negotiation,  execution  and
delivery of this Amendment and the other  documents  contemplated  hereby.  Upon
acceptance  hereof  by the Agent and the  Banks in the  manner  hereinafter  set
forth,  this  Amendment  shall  be  a  contract  between  us  for  the  purposes
hereinabove set forth.

Dated as of December 10, 1998.
MAVERICK TUBE CORPORATION


By  /s/ Gregg Eisenberg
Its  President



Accepted and agreed to as of the day and year last above written.


HARRIS TRUST AND SAVINGS BANK,
individually and as Agent


By   /s/ Donald Busse
Its Vice President



MERCANTILE BANK NATIONAL ASSOCIATION


By   /s/ David Higbee
Its Vice President