NEW YORK -- Alpha Diallo hit a go-ahead jumper with 2:22 left in overtime and fifth-seeded Providence rallied from a 17-point second-half deficit to stun top-seeded and No. 3 Xavier 75-72 in the semifinals of the Big East tournament on Friday night.
Kyron Cartwright hit a clutch jumper with 55 seconds to go and took an offensive foul on a layup attempt by J.P. Macura with eight seconds to play as the Friars (21-12) beat the Musketeers (28-5) for the second time in three games this season.
This one was totally unexpected after the opening 25 minutes at Madison Square Garden. The win sent Providence to the title game against the winner of the second semifinal between second-seeded and No. 2 Villanova and sixth-seeded Butler.
Cartwright's jumper gave Providence a 73-70 lead, but Trevon Bluiett cut the margin to a point with two free throws with 41 seconds to go.
Isaiah Jackson missed a layup attempt with about 12 seconds to play and the Musketeers rushed the ball upcourt. Macura went to the rim, but Cartwright stood his ground and drew the offensive foul call from referee Jeff Anderson.
Diallo added two free throws with six seconds to go, but Xavier didn't get off a final shot until after the final buzzer when Kerem Kanter hit a shot.
By that time, Providence players were running on the court to celebrate at half court after their second overtime victory in as many days. The Friars edged fourth-seeded Creighton 72-68 on Thursday.
Rodney Bullock, who blocked a potential winning layup attempt by Macura at the end of regulation, and Diallo each had 17 points. Cartwright finished with 15 and Nate Watson, who was a monster in the lane in the second half, had 10 of his 14.
Kanter finished with 18 points for Xavier, which was 9-of-33 in the second half, including 2-of-11 from long range. Bluiett had 13 on 2-of-14 shooting. Freshman Paul Scruggs had a career-high 15 points on his birthday, including 13 in the first half when Xavier built a 14-point lead.
Providence, which is seeking its fifth straight NCAA tournament berth, staged one of the best comebacks in Big East tournament history, rallying from a 17-point second-half deficit to tie the score three times in the final 3:45.
The last time came when Cartwright hit two free throws with 13 seconds to go to knot the score at 68.
After electing not to call a timeout, Xavier rushed the ball up the floor and Macura's layup attempt was blocked by Bullock just before the final horn.
The Friars had used 29-12 run to tie the score at 64-all on jumper by Bullock with 3:45 to play. Cartwright had eight points in the run and Watson seven.
A 3-pointer by Macura with 14:45 had extended the Musketeers' lead to 52-35.
Celebrating his 65th birthday, Xavier President Fr. Michael Graham was at the game. ... Seton Hall coach Kevin Willard, who had hoped his third-seeded Pirates would be in the semifinals, was added to the Fox Sports pregame show after the Pirates lost to Butler in the quarterfinals.
Providence: Will play in the title game against either second-seeded and No. 2 Villanova or Butler on Saturday evening. This is its third trip to the championship game, and it won the other two (1994 and 2014).
Xavier: Will probably get a No. 1 seed in the NCAA tournament.