Highlights for the second quarter 2009 include:    --  Production commenced from the Geauxpher field on Garden Banks Block       462 less than a year from discovery with initial gross production       rates of approximately 115 million cubic feet of natural gas       equivalent per day (MMcfe/d).  The field, which is located in water       depths of 2,700 feet, is currently producing approximately 105       MMcfe/d.   --  Success at Mariner's Deadwood exploration play in West Texas with the       evaluation of results from initial production tests and the addition       of 2,000 net acres to the company's position in the Permian Basin.   --  Mariner raised net proceeds of approximately $446 million through       concurrent equity and debt offerings to improve the company's       liquidity and reduce its overall leverage.   --  Mariner collected payment on approximately $50 million of insurance       claims relating to hurricane damage and anticipates additional       collections in the second half of the year.   --  In the first six months of 2009, Mariner generated more than $280       million in operating cash flow (please see end of this release for       prior year data and reconciliation of this non-GAAP measure).    --  Owing to positive results in the company's liquidity, improvement in       oil prices, and reductions in service costs, Mariner recently       increased its 2009 capital program by approximately $50 million       predominantly to fund, oily, long-life projects in the Permian Basin.   

"During the second quarter we increased production from first quarter 2009 and proactively fortified our balance sheet. We are in the enviable position of strong cash flow and excellent liquidity, enabling us to weather events outside our control and capitalize on opportunities that may develop in this challenging environment," said Scott D. Josey, Mariner's Chairman, Chief Executive Officer and President.

SECOND QUARTER 2009 RESULTS

For the three-month period ended June 30, 2009, Mariner reported net income of $17.2 million, or $0.19 per basic and fully-diluted share. This compares with net income of $123.4 million and basic and fully-diluted earnings per share of $1.40 and $1.39, respectively, for the same three-month period in the prior year. The lower year-over-year results are due primarily to lower commodity prices and decreased production volumes.

Net production for second quarter 2009 was 32.9 billion cubic feet of natural gas equivalent (Bcfe), compared with 36.4 Bcfe for second quarter 2008. Total natural gas net production for second quarter 2009 was 23.8 billion cubic feet (Bcf), compared with 24.4 Bcf for the same period in the prior year. Total net oil production for second quarter 2009 was 1.2 million barrels (MMBbls), compared with 1.5 MMBbls for the same period in 2008. Natural gas liquids (NGL) net production for second quarter 2009 was 0.3 MMBbls, compared with 0.5 MMBbls for second quarter 2008.

For second quarter 2009, Mariner's average realized natural gas price was $5.98 per thousand cubic feet (Mcf) compared with $10.27 per Mcf for the same period in 2008. Mariner's average realized oil price was $66.91 per barrel (Bbl) for second quarter 2009, compared with $96.24 per Bbl for second quarter 2008. The average realized NGL price was $24.68 per Bbl for second quarter 2009, compared with $64.69 per Bbl for the same period in 2008. Average realized prices reflect settlements during the period under Mariner's hedging program.

   OPERATIONAL UPDATE    Offshore   

Mariner drilled three offshore wells in the second quarter 2009, one of which was successful:

                                                    Water                                         Working    Depth   Well Name                  Operator   Interest   (Ft)   Location   ---------                  --------   --------   ----   --------   Vermillion 380 A16 ST 2    Mariner     100.0%    340    Conventional Shelf   

Unsuccessful wells during the second quarter included Mariner's Cordage deep shelf prospect (West Cameron 207) and a non-operated well at South Timbalier 316A4.

Subsequent to the end of second quarter 2009, Mariner drilled two wells, one of which was successful:

                                                    Water                                         Working    Depth   Well Name                  Operator   Interest   (Ft)   Location   ---------                  --------   --------   ----   --------   Vermillion 380 A3 ST1      Mariner     100.0%    340    Conventional Shelf   

Mariner's Arden prospect (Garden Banks 949) reached its target depth after quarter end and was determined to be unsuccessful.

Onshore

In the second quarter of 2009, Mariner drilled seven wells in the Permian Basin, all of which were successful. As of August 1, 2009, one rig was operating on Mariner's Permian Basin properties.

CONFERENCE CALL TO DISCUSS RESULTS

A conference call has been scheduled for 11:00 a.m. Eastern Time (10:00 a.m. Central Time) on Friday, August 7, 2009, to discuss second quarter 2009 financial and operating results.

To participate in the call, please dial one of the numbers listed below at least 10 minutes prior to the scheduled start time:

         Callers from the United States and Canada:      +1 (866) 804-6929         Callers from International locations:           +1 (857) 350-1675.    The conference passcode for both numbers is 6009 5145.   

The call also will be webcast live over the Internet and can be accessed through the Investor Information section of Mariner's website at http://www.mariner-energy.com/. A telephonic replay of the call will be available through August 17, 2009 by dialing (888) 286-8010 or (617) 801-6888, pass code 4318 3816. An archive of the webcast will be available shortly after the call on Mariner's website through September 30, 2009.

About Mariner Energy, Inc.

Mariner Energy, Inc. is an independent oil and gas exploration, development and production company headquartered in Houston, Texas, with principal operations in the Permian Basin and the Gulf of Mexico. For more information about Mariner, please visit its website at http://www.mariner-energy.com/.