Fans of the Ivy League's newly launched basketball tournament got everything they wanted. And after years of fading embers, the conference's signature rivalry got a jolt that will live long in the memory.

Penn gave top seed Princeton all it could handle and then some in the tournament's first men's semifinal Saturday. But the Tigers showed the mettle that made them this year's champions, earning a 72-64 overtime win at a thunderously loud Palestra.

Princeton (22-6) will play No. 3 seed Yale in the tournament final at noon Sunday (ESPN2). After going 14-0 in conference play, the Tigers are one win away from the NCAA tournament - and that game could well be easier than Saturday's was.

With 6 minutes, 9 seconds to go in the first half, Penn guard Ryan Betley hit a three-pointer to put the Quakers up, 28-19.

Princeton clawed to within 33-30 at halftime. But Penn (13-15) regained its momentum after intermission, pushing its lead to 44-34 with just over four minutes played. Displeased Tigers coach Mitch Henderson called a timeout that proved pivotal.

"We just said, 'Look, what are we going to do here?' " Henderson said after the game. "We were just getting pounded, haymaker after haymaker, and I think just got fed up with it."

That anger got channeled into a ferocious defensive effort. Princeton held the Quakers to just two made field goals over the next 71/2 minutes, and finally tied the game at 49-49 with 8:18 to go.

"We all knew, even when we were up 10, that this is a really, really good basketball team with veteran leadership that knows how to win," Penn coach Steve Donahue said. "I knew we were going to get another punch. I think our guys knew that too."

Yet as the clock ticked down, Princeton still couldn't take the lead. And when Penn's Matt Howard hit a floater with 43 seconds remaining - after the ball bounced on the rim three times - it seemed that the Tigers might never. Even more so when Princeton's Steve Cook missed a wide-open, short-range baseline jumper on the ensuing possession.

But after Howard missed the front end of a one-and-one, the Tigers raced down the floor, and Myles Stephens put back Amir Cook's missed drive to send the game to overtime.

It was all Tigers from there, starting when Stephens finally put them ahead on their first possession of the extra session. He was the game's top scorer with 21 points, and added 10 rebounds.

Betley led Penn with 18 points and 12 rebounds.

Yale 73, Harvard 71 - The No. 3-seeded Bulldogs upended the second-ranked Crimson in a game that was every bit as thrilling as the classic rivalry in the other semifinal.

Yale led from start to finish, including by as many as 13 points just over three minutes into the second half. But Harvard rallied, led by freshman guard Bryce Aiken. This season's Ivy League rookie of the year scored 20 of his game-high 28 points from that point.

Yale was led by its own freshman star, guard Miye Oni, who delivered 18 points and six rebounds.