MEMPHIS, DEC. 27 -- It may be called the Air Force Academy, but Coach Fisher DeBerry's Falcons don't strike through the air.

Instead, the Falcons prefer the rough and rugged ground game displayed tonight as they upset No. 24 Ohio State, 23-11, in the Liberty Bowl.

Air Force, led by quarterback Rob Perez's 93 yards on 26 carries, ran 61 times for 254 yards while passing only three times, completing one for 11 yards and having one intercepted.

The Falcons (7-5), a 17-point underdog, built a 13-5 lead on a pair of one-yard touchdown runs by Perez. After Ohio State (7-4-1) got back within two points, Carlton McDonald put the game away with his second interception.

"I thought Perez did an excellent job of moving the team," DeBerry said. "In my opinion, {it was} one of the greatest wins in the history of Air Force Academy football. We proved we deserved to be here. I don't know if I've ever been prouder of a team."

Despite having a weight advantage of about 50 pounds a man along the line of scrimmage, Ohio State had trouble running against the quicker Falcons.

The Buckeyes finally found the end zone with 13:21 to play on a 29-yard run by Robert Smith. Quarterback Kent Graham, replacing starter Greg Frey, moved Ohio State 69 yards in four plays to make it 13-11.

Ohio State went for a tying two-point conversion, but Graham overthrew Bobby Olive.

Air Force responded with a time-consuming drive, but Perez and fullback Rodney Lewis mishandled a handoff and Ohio State's Jim Peel recovered at the Buckeyes 12 with 6:59 left.

Air Force frustrated the Ohio State passing game, chasing Frey out of the pocket repeatedly and finally forcing a punt. When Jeff Bohiman's kick went only 12 yards, Air Force had the ball at the Ohio State 36 with another opportunity to lock up the game.

This time Joe Wood kicked a 46-yard field goal for a 16-11 lead with 2:47 to play.

Forced by Wood's kick to score a touchdown rather than move into position for a field goal, Ohio State came out passing. McDonald was waiting for Frey's pass to the sideline and ran untouched to the Ohio State end zone.

Ohio State dominated the opening minutes of play, converting a bad punt snap into a safety and driving to a field goal for a 5-0 lead.

Air Force failed to move after taking the opening kickoff, and Jason Christ came on to punt from the Falcons 33-yard line.

Center Louis Yeager's snap sailed over Christ's head, and by the time he retrieved the ball he was surrounded. Craig Griffey brought him down in the end zone for a safety 2:03 into the game.

Ohio State started from its 45 after the free kick and, after twice keeping the drive going with fourth-and-one runs, settled for Tim Williams's 28-yard field goal.

The Buckeyes had the Falcons on the ropes minutes later, when Bobby Thomas muffed a punt and Ohio State's Vinnie Clark recovered at the Buckeyes 45.

Ohio State moved to the Air Force 15, but Frey was sacked by Virgil Simpson and Williams missed a 43-yard field goal attempt.