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                                                                   EXHIBIT 10.21

                               THIRD AMENDMENT TO
                           FOURTH AMENDED AND RESTATED
                                CREDIT AGREEMENT

          This THIRD AMENDMENT TO FOURTH AMENDED AND RESTATED CREDIT AGREEMENT
("Amendment") is made its of November __, 1998, by and among COHO RESOURCES,
INC., a Nevada corporation ("CRI"), COHO LOUISIANA PRODUCTION COMPANY, a
Delaware corporation (the "Production Company"), COHO EXPLORATION, INC., a
Delaware corporation ("Exploration") COHO OIL & GAS, INC. (formerly named Coho
Acquisition Company), a Delaware corporation ("Oil & Gas"). (CRI, the Production
Company, Exploration and Oil & Gas are sometimes collectively referred to as the
"Borrowers" and individually as a "Borrower"), COHO ENERGY, INC., a Texas
corporation ("Holdings") (the Borrowers and Holdings are sometimes referred to
herein together as the "Companies" or individually as a "Company"), those banks
or other lending institutions which are signatory hereto and which constitute
the Required Lenders as provided in the Original Agreement (as defined below)
(collectively, the "Required Lenders"), PARIBAS, a bank organized under the laws
of the Republic of France acting through its Houston Agency ("PARIBAS") in its
capacity as Administrative Agent for the Lenders (in such capacity, together
with its successors in such capacity, the "Administrative Agent"), and BANK ONE,
N.A., a national banking association (successor by merger to Bank One, Texas,
N.A. and referred to herein as "Bank One"), and MEESPIERSON CAPITAL CORP., a 
Delaware corporation ("MeesPierson"), as Co-Documentation Agents for the Lenders
(Bank One and MeesPierson in such capacities, together with their successors in
such capacities, the "Co-Documentation Agents").

                                R E C I I A L S

          A. The parties hereto and certain other banks and lending institutions
(the "Other Lenders") entered into that certain FOURTH AMENDED AND RESTATED
CREDIT AGREEMENT dated as of December 18, 1997, as amended by that certain FIRST
AMENDMENT TO FOURTH AMENDED AND RESTATED CREDIT AGREEMENT dated as of July 7,
1998 and by that certain SECOND AMENDMENT TO FOURTH AMENDED AND RESTATED CREDIT
AGREEMENT dated as of November 13, 1998 (as so amended, the "Original
Agreement") pursuant to which the Lenders agreed to lend the Borrowers a maximum
of Three Hundred Million Dollars ($300,000,000.00) pursuant to the terms and
conditions thereof.

          B. The Borrowers and its Affiliates which are parties to the Original
Agreement have requested that the Original Agreement be amended and modified in
certain respects as provided herein, which request has been approved by those
Lenders which constitute the Required Lenders.

          NOW, THEREFORE, in consideration of the premises and the mutual
covenants herein contained, the parties hereto agree as follows:



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          1. Terms. All capitalized terms used herein and not specifically
defined herein shall have the meanings given them in the Original Agreement.

          2. Consent to Sale of Properties. The Required Lenders hereby agree
and consent (a) to the sale of the properties described on EXHIBIT A attached
hereto and incorporated herein (the "Sale Properties"), all of the proceeds of
which sale will be used to pay against the Notes in accordance with the terms of
the Original Agreement, and (b) to release the Sale Properties from the Lien in
favor of the Administrative Agent and the Lenders against receipt of the
proceeds of such sale.

          3. Borrowing Base and Threshold Amount. For the period from July 7,
1998 until the "Threshold Amount Termination Date" (as such term is defined
below), the (a) Borrowing Base shall be Two Hundred Forty-Two Million Dollars
($242,000,000), and (b) the Threshold Amount shall be Two Hundred Twenty Million
Dollars ($220,000,000.00); provided, however, if before the Threshold Amount
Termination Date, a redetermination of the Borrowing Base should be required
pursuant to Section 2.10(e), the Borrowing Base and the Threshold Amount shall
be redetermined by the Supermajority Lenders in accordance the standards set
forth in Section 2.10(f). Such redeterminations shall be effective until the
Threshold Amount Termination Date, at which time (x) the applicability of the
Threshold Amount shall no longer apply to the Agreement and (y) all
redeterminations of the Borrowing Base, if any, shall thereafter be made in
accordance with Section 2.10 of the Agreement. As used in this Section 3, the
term "Threshold Amount Termination Date" shall mean the earlier of:

          (i)     30 days following the closing of the $250 million investment 
                  in CRI by HM4 Coho, LP, a Texas limited partnership managed by
                  Hicks Muse ("Hicks Muse");

          (ii)    30 days following a vote by the shareholders of CRI rejecting 
                  the Hicks Muse proposal; or

          (iii)   January 31, 1999.

          4.      Miscellaneous.

          4.1 Headings. Section headings are for reference only and shall not
affect the interpretation or meanings of any provision of this Amendment.


          4.2 Effect of this Amendment. The Original Agreement, as amended by
this Amendment, shall remain in full force and effect except that any reference
therein, or in any other Loan Document referring to the Original Agreement, 
shall be deemed to refer to the Original Agreement as amended by this Amendment.

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         4.3 GOVERNING LAW. THIS AMENDMENT SHALL BE GOVERNED BY, AND CONSTRUED
IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK AND APPLICABLE FEDERAL
LAW.

         4.4 Counterparts. This Amendment may be executed by the different
parties hereto on separate counterparts, each of which, when so executed, shall
be deemed an original but all such counterparts shall constitute but one and the
same Amendment.

         4.5 NO ORAL AGREEMENTS. THE ORIGINAL AGREEMENT, AS AMENDED BY THIS
AMENDMENT, TOGETHER WITH THE OTHER LOAN DOCUMENTS, REPRESENTS THE ENTIRE
AGREEMENT AMONG THE PARTIES AND MAY NOT BE CONTRADICTED BY EVIDENCE OF PRIOR
CONTEMPORANEOUS, OR SUBSEQUENT ORAL AGREEMENTS OF THE PARTIES. THERE ARE NO
UNWRITTEN ORAL AGREEMENTS BETWEEN OR AMONG THE PARTIES.

         4.6 Representations. The Borrowers hereby represent and warrant (a)
that they have the corporate power and authority to enter into and perform their
obligations under this Agreement, (b) that their execution, delivery and
performance of this Agreement have been duly authorized by all necessary
corporate acts on the part of each, and (c) that no Event of Default or
Potential Default exists.

         IN WITNESS WHEREOF, the Borrowers, Holdings, the Administrative Agent,
the Co-Documentation Agents and the Lenders have executed this Agreement as of
the date first written above

                                     BORROWERS:                           
                                     
                                     COHO RESOURCES, INC.
                                     
                                     By:
                                        -------------------------------
                                        Eddie M. LeBlanc, III
                                        Senior Vice President and
                                        Chief Financial Officer
                                     
                                     
                                     COHO LOUISIANA PRODUCTION COMPANY
                                     
                                     By:
                                        -------------------------------
                                        Eddie M. LeBlanc., III
                                        Senior Vice President and
                                        Chief Financial Officer


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