Pioneer & Evergreen Get Stockholder Approval for Merger

Pioneer Natural Resources and Evergreen Resources announce that at their respective special meetings of stockholders held today, holders of approximately 76% of the total outstanding shares of Pioneer common stock voted in favor of the issuance of shares of Pioneer common stock in connection with Pioneer's merger with Evergreen, and holders of approximately 67% of the total outstanding shares of Evergreen common stock voted to approve the merger agreement with Pioneer. In both cases, of the votes cast, over 99% were in favor of the transaction.

Pursuant to the merger, Evergreen will become a subsidiary of Pioneer and Evergreen stockholders will receive new shares of Pioneer common stock and cash.

Pioneer expects the merger to be completed later today when the required governmental filing is made in Colorado.

Pioneer Natural Resources is a large independent oil and gas exploration and production company with operations in the United States, Argentina, Canada, Equatorial Guinea, Gabon, South Africa and Tunisia. Pioneer's headquarters are in Dallas.

Evergreen is an independent energy company engaged primarily in the exploration and development of unconventional natural gas properties. Evergreen is one of the leading developers of coal bed methane reserves in the United States with current operations primarily focused on developing and expanding gas reserves in the Raton Basin in southern Colorado. Evergreen's headquarters are in Denver.

Pioneer and Evergreen have filed with the SEC a registration statement containing the joint proxy statement-prospectus used by Pioneer and Evergreen to solicit approval of its stockholders to issue additional stock in the merger and used by Evergreen to solicit the approval of its stockholders for the proposed merger. Pioneer has also filed other documents concerning the proposed merger. You are urged to read the registration statement and the joint proxy statement-prospectus regarding the proposed merger because they contain important information. You can obtain a free copy of the joint proxy statement-prospectus including the registration statement, as well as other filings containing information about Pioneer at the SEC's website. Copies of the joint proxy statement-prospectus can also be obtained without charge, by directing a request to: Pioneer Natural Resources Company, Susan Spratlen, 5205 N. O'Connor Blvd., Suite 900, Irving, Texas 75039, or via telephone at 972-969-3583.