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                                                                     Exhibit 5.1
                             [LOGO VINSON & ELKINS]
                                ATTORNEYS AT LAW

                              VINSON & ELKINS LLP
                           3700 TRAMMELL CROW CENTER
                                2001 ROSS AVENUE
                            DALLAS, TEXAS 75201-2975
                            TELEPHONE (214) 220-7700
                               FAX (214) 220-7716




                                 October 8, 1999


Range Resources Corporation
500 Throckmorton Street
Fort Worth, Texas  76102

Ladies and Gentlemen:

         We have acted as counsel for Range Resources Corporation, a Delaware
corporation and formerly "Lomak Petroleum, Inc." (the "Company"), in connection
with the Company's registration under the Securities Act of 1933, as amended
(the "Act"), of 475,000 shares of common stock, par value $0.01 per share, of
the Company (the "Shares") which may be purchased in the open market and offered
from time to time under the Range Resources Corporation 1997 Stock Purchase Plan
(the "Plan") under the Company's Registration Statement on Form S-8 filed with
the Securities and Exchange Commission (the "Commission") on October 8, 1999.

         In reaching the opinions set forth herein, we have examined and are
familiar with originals or copies, certified or otherwise identified to our
satisfaction, of such documents and records of the Company and such statutes,
regulations and other instruments as we deemed necessary or advisable for
purposes of this opinion, including (i) the Registration Statement, (ii) the
Certificate of Incorporation of the Company, as filed with the Secretary of
State of the State of Delaware, (iii) the Bylaws of the Company, (iv) certain
minutes of meetings of, and resolutions adopted by, the Board of Directors of
the Company and the Company's stockholders authorizing the issuance and offering
of the Shares in the Plan and (v) the Plan.

         We have assumed that (i) all information contained in all documents we
reviewed is true, correct and complete, (ii) all signatures on all documents we
reviewed are genuine, (iii) all documents submitted to us as originals are true
and complete, (iv) all documents submitted to us as copies are true and complete
copies of the originals thereof, and (v) all persons executing and delivering
the documents we examined were competent to execute and deliver such documents.

         Based on the foregoing, and having due regard for the legal
considerations we deem relevant, we are of the opinion that the Shares, when
offered and issued by the Company pursuant to the terms of the Plan, will be
validly issued, fully paid and non-assessable.



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         This opinion is limited in all respects to the laws of the Delaware
General Corporation Law and the federal laws of the United States of America.


         This opinion letter may be filed as an exhibit to the Registration
Statement. In giving this consent, we do not thereby admit that we come within
the category of persons whose consent is required under Section 7 of the Act or
the rules and regulations of the Commission promulgated thereunder.

                                           Very truly yours,



                                           VINSON & ELKINS L.L.P.





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