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                                                                    EXHIBIT 99.1


FOR IMMEDIATE RELEASE            Contacts:     Jonathan D. (Jody) Nelson, CFO
---------------------                          Patterson Energy, Inc.
                                               (915) 573-1104

                                               John Vollmer, CFO
                                               UTI Energy Corp.
                                               (281) 873-4111


                  PATTERSON ENERGY/UTI ENERGY MERGER COMPLETED

         COMBINATION CREATES SECOND-LARGEST LAND-BASED DRILLING FLEET IN
                                 NORTH AMERICA

                  COMPANY ANNOUNCES NEW SENIOR MANAGEMENT TEAM


         SNYDER, TEXAS AND HOUSTON, TEXAS - MAY 8, 2001 -- PATTERSON ENERGY,
INC. (NASDAQ: PTEN) AND UTI ENERGY CORP. (AMEX: UTI) today announced that their
shareholders had approved a merger that creates North America's second-largest
operator of land-based oil and gas drilling rigs. Shortly after the approvals,
the merger was completed and the surviving company was renamed "Patterson-UTI
Energy, Inc." Its common shares will be traded on NASDAQ under the symbol
"PTEN", with approximately 76 million common shares outstanding.

         Under terms of the merger, shareholders of UTI Energy will receive one
share of Patterson Common Stock for each share of UTI Common Stock. As of the
close of the market on Monday, May 7, 2001, the companies had a combined market
valuation of $2.2 billion.

         The combined companies, headquartered in Snyder, Texas, have 302
land-based drilling rigs, of which 286 are located in the United States and 16
rigs in Western Canada.


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         Patterson-UTI also announced that Mark S. Siegel, who had served as
Chairman of UTI, has been appointed Chairman of Patterson-UTI. Cloyce A.
Talbott, who formerly served as Chairman and Chief Executive Officer of
Patterson, will serve as Chief Executive Officer. In addition, Glenn Patterson,
will be President and Chief Operating Officer; Jonathan D. (Jody) Nelson, will
be Chief Financial Officer; and John Vollmer, who had been UTI's current Chief
Financial Officer, assumes the title of Senior Vice President - Corporate
Development. Vaughn Drum, a founder of UTI who had served as UTI's Chief
Executive Officer for 14 years, has elected to retire. Mr. Drum has been
involved in the oil service industry for 35 years.

         "With more than 300 land-based drilling rigs strategically located in
some of the most prolific oil- and gas-producing regions in North America,
Patterson-UTI will have the second-largest land-based drilling fleet in North
America," said Mr. Talbott. "Moreover, our combined rig fleet, well-matched to
the drilling activity in North America, together with the strengths of the
combined management teams, provide us with flexibility and capacity to meet the
drilling needs of an expanded customer base," Mr. Talbott added.

         Mr. Siegel said, "This is a very exciting day for the shareholders of
both companies. Both UTI and Patterson built shareholder value through the
consistent implementation of growth strategies through the various cycles of our
business. We believe that the combined resources of both companies will provide
an even stronger base for further growth and consolidation."

         Commenting on Vaughn Drum's retirement, Mr. Siegel said, "Vaughn's many
contributions have been enormous and greatly appreciated. We wish him health and
happiness in the years ahead."

         Mr. Drum said, "Even before the merger was negotiated, I had decided to
retire to spend more time with my family. I am gratified that UTI has been able
to hook up with a great industry partner, and look forward to serving as
director of the new, combined Company. I am highly confident that the transition
will be both smooth and seamless, and I wish the new management team nothing but
success going forward."


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ABOUT PATTERSON-UTI

         Patterson-UTI Energy, Inc., headquartered in Snyder, Texas, is the
second-largest provider of domestic land-based drilling services to major
independent oil and natural gas companies in North America. The Company owns 302
drilling rigs, with drilling operations in Texas, New Mexico, Utah, Oklahoma,
Louisiana and western Canada. The company is also engaged in the business of
pressure pumping; oil and gas exploration and production; and drilling and
completion fluids services.

Statements made in this press release which state the Company's or management's
intentions, beliefs, expectations or predictions for the future are
forward-looking statements. It is important to note that actual results could
differ materially from those discussed in such forward-looking statements.
Important factors that could cause actual results to differ materially include,
but are not limited to, declines in oil and natural gas prices that could
adversely affect demand for the Company's services, and their associated effect
on day rates, rig utilization and planned capital expenditures, adverse industry
conditions, difficulty in integrating acquisitions, demand for oil and natural
gas, and ability to retain management and field personnel. Additional
information concerning factors that could cause actual results to differ
materially from those in the forward-looking statements is contained from time
to time in the Company's SEC filings, including but not limited to, the
Patterson Energy's and UTI Energy's reports on Form 10-K for the year ended
December 31, 2000 and Forms 10-Q for fiscal 2001 reporting periods. Copies of
these filings may be obtained by contacting the Companies or the SEC.