Exhibit 10.23

                            MAVERICK TUBE CORPORATION
                   NINTH AMENDMENT TO SECURED CREDIT AGREEMENT


Harris Trust and Savings bank
Chicago, Illinois

Mercantile Bank National Association
   (formerly known as Mercantile Bank of St. Louis
    National Association)
St. Louis, Missouri

Ladies and Gentlemen:

             Reference is hereby made to that certain  Secured Credit  Agreement
dated as of May 15, 1992, as heretofore  amended (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.

         Concurrently herewith the Borrower is transferring all or substantially
all of its assets and  liabilities  to Maverick Tube,  L.P., a Delaware  limited
partnership  ("L.P.")  in which  Maverick  Investment  Corporation,  A  Delaware
corporation ("Investment") and a wholly-owned subsidiary of the Borrower, is the
sole  limited  partner and in which the  Borrower is the sole  general  partner,
having a 95% and 5% equity interest,  respectively,  therein. In connection with
such  transfers  the Banks have  required the L.P. and  Investment  guaranty the
payment  when  due  of  all  of the  Borrower's  indebtedness,  obligations  and
liabilities  to the  Banks.  The  Borrower,  the Agent and the Banks now wish to
amend the Credit  Agreement to reflect such  transfers and such guaranty by L.P.
and Investment, all on 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 of the Credit Agreement shall be amended by adding 
thereto the following definitions:

                  ""Guarantors"  shall  mean  Maverick  Tube  L.P.,  a  Delaware
limited   partnership,   and  Maverick   Investment   Corporation,   A  Delaware
corporation, and "Guarantor" shall mean any of the Guarantors.

                  "Subsidiary  Guaranty" shall mean the Guaranty Agreement dated
as of  October  1, 1997 from the  Guarantors  to the  Banks,  as the same may be
supplemented and amended from time to time."

         1.2 Section 4.50 of the Credit Agreement shall be amended by adding the
phrase  "the  Subsidiary  Guaranty,"  after the phrase  "the  Revolving  Notes,"
appearing therein.

         1.3      Section 5.9 of the Credit  Agreement  shall be amended and as
so amended  shall be restated in its entirety to read as
follows:

     "Section  5.9.  Subsidiaries.  As  of  the  date  hereof,  the  Borrower's 
     only Subsidiaries are identified on Exhibit E hereof.  Each of said 
     Subsidiaries is duly  organized  and  validly  existing  under  the laws of
     the state or country of its  incorporation,  has full and  adequate  cor-
     porate  power to carry on its business as now conducted, is duly licensed 
     or qualified to do business in all jurisdictions wherein the nature of its 
     activities requires such licensing or  qualification  except when the fail-
     ure to be so licensed or  qualified  would not have  material  adverse  
     effect on the  condition, financial or otherwise, of such Subsidiary.  Each
     Guarantor has full right, power and authority to enter into the Subsidiary
     Guaranty,  to guaranty the payment of the Borrower's indebtedness,  obliga-
     tions and liabilities to the Agent and the Banks,  and to perform each and 
     all of the matters and things therein  provided for; and the  Subsidiary  
     Guaranty does not, nor does the performance  or observance by any Guarantor
     of any of the matters or things provided  for  therein,  contravene  any  
     provision  of law or any charter, partnership  agreement or b-law  provi-
     sion or any  covenant,  indentures or agreement of or judgment,  order or 
     decree  applicable  to or affecting any Guarantor or any of their 
     respective Property."
     
    1.4      Section 5.11 of the Credit  Agreement  shall be amended and as so 
amended shall be restated in its entirety to read as follows:

         "Section  5.11.  Enforceability.  This  Agreement,  when  executed  and
         delivered by the Borrower, will be a legal, valid and binding agreement
         of the Borrower,  enforceable  against it in accordance with its terms,
         except as may be limited by (i) bankruptcy, insolvency, reorganization,
         fraudulent  transfer,  moratorium  or other  similar  laws or  judicial
         decisions  for the relief of debtors or the  limitation  of  creditors'
         rights  generally;  and (ii) any  equitable  principles  relating to or
         limiting the rights of  creditors  generally  or any  equitable  remedy
         which may be granted to cure any defaults; and the Revolving Notes, the
         other Loan  Documents  to which the  Borrower  is a party and any other
         instrument or agreement  required  hereunder to which the Borrower is a
         party has been so authorized and, when executed and delivered,  will be
         similarly valid,  binding and enforceable against the Borrower,  except
         as  may  be  limited  by (i)  bankruptcy,  insolvency,  reorganization,
         fraudulent  transfer,  moratorium  or other  similar  laws or  judicial
         decisions  for the relief of debtors or the  limitation  of  creditors'
         rights  generally;  and (ii) any  equitable  principles  relating to or
         limiting the rights of  creditors  generally  or any  equitable  remedy
         which may be granted to cure any defaults; and the Subsidiary Guaranty,
         when executed and delivered by each Guarantor,  will be a legal,  valid
         and binding  agreement  of such  Guarantor,  enforceable  against it in
         accordance with its terms,  except as may be limited by (i) bankruptcy,
         insolvency,  reorganization,  fraudulent transfer,  moratorium or other
         similar  laws or  judicial  decisions  for the relief of debtors or the
         limitation  of  creditors'  rights  generally;  and (ii) any  equitable
         principles relating to or limiting the rights of creditors generally or
         any equitable remedy which may be granted to cure any defaults.

         1.5 Section 7.15 of the Credit  Agreement  shall be amended by deleting
the word "and"  appearing  after the  semi-colon  at the end of  subsection  (i)
thereof,  by replacing the period appearing at the end of subsection (j) thereof
with the  phrase  "; and" and by  adding  thereto  the  following  provision  as
subsection (k) thereof:

         "(k)     indebtedness of the Guarantors to the Borrower and indebted-
         ness of the Guarantors to the Agent and the Banks under the Subsidiary
         Guaranty."

         1.6 Section 7.16 of the Credit  Agreement  shall be amended by deleting
the word "and"  appearing  after the  semi-colon  at the end of  subsection  (g)
thereof,  by replacing the period appearing at the end of subsection (h) thereof
with the  phrase  "; and" and by  adding  thereto  the  following  provision  as
subsection (i) thereof:

         "(i)     investments in and loans and advances to the Guarantors."

         1.7 Section 7.17 of the Credit  Agreement  shall be amended by deleting
the word "and"  appearing  after the  semi-colon  at the end of  subsection  (a)
thereof,  by replacing the period appearing at the end of subsection (b) thereof
with the  phrase  "; and" and by  adding  thereto  the  following  provision  as
subsection (c) thereof:

         "(c)     the transfer of all or substantially all of the Borrower's 
         assets and liabilities to the Guarantors."

         1.8      The Credit Agreement shall be amended by adding the following
         provision thereto as Section 7.26 thereof:

         "Section 7.26.  Guarantor Collateral.  No later than November 30, 1997,
         each Guarantor shall grant to the Agent for the benefit of the Banks a
         security interest in its inventory  and  accounts  and related  proper-
         ties  pursuant to security agreements substantially identical to the 
         Security Agreement and shall take such actions as the Agent
         may reasonably request in order to perfect the Agent's security 
         interests therein."

         1.9  Section 8.1 of the Credit  Agreement  shall be amended by deleting
the word  "or"  appearing  after the  semi-colon  at the end of  subsection  (h)
thereof,  by replacing the period appearing at the end of subsection (i) thereof
with  the  phrase  "; or" and by  adding  thereto  the  following  provision  as
subsection (j) thereof.:

         "(j) Any  Guarantor  shall  breach,  repudiate,  disavow  or purport to
         terminate its  obligations  under the  Subsidiary  Guaranty or any part
         thereof,  or the Subsidiary  Guaranty or any part thereof shall for any
         reason not be the legal,  valid and binding obligation of any Guarantor
         Subsidiary."

         1.10     Exhibit E to the Credit Agreement shall be replaced by Exhibit
         E attached to this Amendment.

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      L.P. and Investment shall have executed and delivered to the 
Agent for the benefit of the Banks a Guaranty  Agreement satisfactory in form 
and substance to each of the Banks.

         2.3      The Agent for the benefit of the Banks shall have received:

         (a) a good standing  certificate  or  certificate  of existence for the
         Borrower  and  each  Guarantor  dated as of the  date no  earlier  than
         September  1, 1997,  from the office of the  Secretary  of State of the
         states of their respective organization;

         (b)  copies of the  Certificate  of  Incorporation  or  Certificate  of
         Limited  Partnership,  and all amendments  thereto,  of each Guarantor,
         certified by the office of the Secretary of State of Delaware as of the
         date no earlier than September 1, 1997.

         (c) copies of the  By-Laws or Limited  Partnership  Agreement,  and all
         amendments  thereto,  of each Guarantor  certified as true, correct and
         complete on the date hereof by the Secretary of each Guarantor;

         (d) copies,  certified by the  Secretary or Assistant  Secretary of the
         Borrower and each Guarantor,  of resolutions regarding the transactions
         contemplated by this Amendment,  duly adopted by the Board of Directors
         of the Borrower an each Guarantor,  respectively,  and  satisfactory in
         form and substance to all of the Banks;

         (e)      an incumbency signature certificate for the Borrower and each
         Guarantor satisfactory in form and substance to all of the Banks; and

         (f) the favorable  written opinions of counsel for the Borrower and the
         Guarantors in form and substance  satisfactory to each of the Banks and
         their respective legal counsel.

         2.4 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.

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

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 Borrowers; 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 Equipment Security Agreement, and the Borrower hereby
agrees that  notwithstanding  the execution and delivery  hereof,  such Security
Agreements  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 or the
Equipment  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 by 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 October 1, 1997.

                                                  MAVERICK TUBE CORPORATION

                                                  By: /s/ Gregg Eisenberg

                                                  Its:  President

                                                  By: /s/ Charles Struckhoff

                                                  Its:  Chief Financial Officer

         Accepted  and agreed to at Chicago,  Illinois,  as of the date and year
last above written.

                                                  HARRIS TRUST AND SAVINGS BANK

                                                  By: /s/ Bonnie A. Polic

                                                  Its:  Vice President


                                                  MERCANTILE BANK   NATIONAL
                                                     ASSOCIATION

                                                  By: /s/ David Higbee

                                                  Its:  Vice President