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                                                                    EXHIBIT 23.1

                        Consent of Independent Auditors


We consent to the incorporation by reference in the Registration Statement (Form
S-8 No. 333-66929) pertaining to the 1998 Key Employee Stock Option Plan of
Vista Energy Resources, Inc. of our reports dated February 11, 2000, with
respect to the consolidated financial statements Prize Energy Corp., and
September 3, 1999, with respect to the producing properties acquired by Prize
Energy Corp. from Pioneer Natural Resources USA, Inc., included in the Annual
Report (Form 10-K) for the year ended December 31, 1999.

                                                  ERNST & YOUNG LLP

Fort Worth, Texas
March 30, 2000