For George Mason and Navy, this year's ECAC South tournament was a short one. Both lost in tonight's first round.

The tournament opened with Richmond beating East Carolina, 49-42. Then Old Dominion, led by Ronnie McAdoo's 24 points, defeated Mason, 70-62. Finally, William and Mary beat Navy, 79-55, in a game that was decided by halftime.

James Madison received a first-round bye as the top seed.

In Friday night's semifinals, ODU will play Richmond and James Madison will meet William and Mary.

Mason (13-14) trailed at the half, 33-24, and when ODU made its first four shots of the second half, the outcome seemed decided.

But with 5:59 left, Mason closed to 56-45 on John Niehoff's layup. After ODU pushed the lead back to 13, the Patriots' 10-2 spree over a two-minute span cut the deficit to 62-57, with 1:52 remaining. Old Dominion helped by missing the front end of three one and ones.

Mason seemed to have a real chance when Andre Gaddy was fouled while making a reverse layup. But he missed the free throw and Mason had no choice but to foul. It didn't work because ODU quit missing foul shots.

Freshman Carlos Yates led the Patriots with 16 points. Andy Bolden had 14.

Billy Mann of ODU scored 16, mostly from the outside. Mark West, ODU's 6-foot-10 center, blocked six shots and had nine rebounds. "West completely dominated the game defensively," Coach Joe Harrington of Mason said. "He was unbelievable."

Navy (12-14) started well as Rob Romaine and David Brooks helped the Midshipmen to a 14-11 lead. But William and Mary shot 68 percent from the field to lead at the half, 38-26.

In the second half the Indians (16-11) worked well inside against the smaller Midshipmen. With a 71-45 lead, the Indians sent in the substitutes.

"We played very good after the first five or six minutes," Coach Bruce Parkhill of William and Mary said.

"We didn't shoot well tonight," Navy Coach Paul Evans said. "And when you don't defend well either, you are going to be in big trouble."

Mike Strayhorn led William and Mary with 14 points. For Navy, Romaine had 17, Brooks 12 and Sly Mata and Gary Price 10 each.