PROVIDENCE--The Princeton Tigers were ready to pull off the biggest upset in NCAA men's basketball tournament history last night, but Alonzo Mourning wouldn't let them.

Mourning hit a free throw with 23 seconds left and made two big defensive plays in the final six seconds as second-ranked George-town escaped with a 50-49 victory in the opening round of the NCAA tournament.

The Tigers, seeded 16th in the East Regional, used a patient spread offense to frustrate the top-seeded Hoyas and build a 10-point lead early in the second half. But the Hoyas rallied behind Mourning, a 6-ft., 10-in. freshman center, who finished with 21 points.

Mourning, who tied the score, 49-49, with a pair of free throws, blocked a three-point attempt by Princeton's Bob Scrabis with six seconds left and tipped a shot by Kit Mueller as the buzzer sounded.

"Before the game, I would have said we would have been happy being so close," Princeton forward Matt Lapin said. "Now, there's a hollow feeling because we saw we could have won it."

The Hoyas (27-4) almost became the first top seed to lose an opening round game in the tournament.