Trevon Bluiett knew what the situation called for, but he wanted to be a little bit diplomatic.

With the score tied and Xavier's season on the line, the junior also knew it wasn't a time to be timid.

Musketeers coach Chris Mack drew up a play for his standout guard and Bluiett drained a 17-foot step-back jumper to cap a 23-point performance and provide Xavier with a crucial 62-57 victory over No. 18 Butler on Thursday in the Big East tournament quarterfinals at New York's Madison Square Garden.

Bluiett's basket with 16.5 seconds left snapped a 57-57 tie to fuel a victory that might lift the Musketeers off the NCAA Tournament bubble. Xavier (21-12) has won three straight games following a six-game losing streak.

"He's done it all year," Mack said. "I put the ball in his hands. It was a little scary because you don't know how early you want to go but not scary when he has the ball and is playing with the mindset he had tonight."

Bluiett ran an isolation play and separated from his defender before knocking down the shot from the elbow. As for how the play was decided, Bluiett called it a "50-50 decision."

"Half me saying, 'C'mon give me the ball,'" Bluiett said. "And half coach."

The Musketeers face Creighton in Friday's semifinals.

Senior guard Malcolm Bernard contributed 12 points and 10 rebounds for seventh-seeded Xavier. Junior center Sean O'Mara added 10 points for the Musketeers, who overcame 17 turnovers.

Junior forward Kelan Martin scored 15 points for the second-seeded Bulldogs (23-8). Senior guard Kethan Savage added 13 points.

"You're going to struggle when you turn the ball over late in the game and allow your opponent to shoot (61.1) percent in the second half," Butler coach Chris Holtmann said. "We had a good way about us tonight, but we just couldn't get it done."

Butler had a chance to recover from Bluiett's big hoop, but freshman guard Kamar Baldwin missed an open 3-pointer with 10 seconds left and senior guard Tyler Lewis missed a free throw-line jumper with five seconds to play.

Xavier added a free throw from junior guard J.P. Macura and a dunk from freshman forward Tyrique Jones to seal it.

The late-game fire is something that personifies the character of the Musketeers, according to Bluiett.

"I think we're relentless," Bluiett said. "We fight through adversity and have been fighting that all season. Coach is telling up to stay the course and we never got distracted and we stayed the course. We know what's ahead. We're a group of tough guys."

Meanwhile, the Bulldogs established a season low for points and dropped to 0-4 all-time in Big East tourney history.

"We play pretty much a good team every time," Holtmann said. "We're not ignoring the fact that we're 0 for 4. We want to win. Our guys want to win. We're disappointed."

Butler tallied just 12 points over the final 12 minutes to aid Xavier's comeback quest.

Martin scored the final five points of an 11-0 surge that saw the Bulldogs take a 45-38 advantage with 12 minutes remaining. The lead was again seven on junior forward Tyler Wideman's layup with 7:55 remaining.

The Bulldogs went scoreless over the next four-plus minutes as Xavier tallied eight straight points to take a 50-49 lead. Butler regained the lead when Baldwin stole the ball from Macura and drove the length of the court for a layup to give the Bulldogs a one-point edge with 3:41 left.

Bluiett answered with a three-point play 25 seconds later to push Xavier back ahead 53-51. The Bulldogs caught the Musketeers at 56 on a driving layup by Savage with 1:07 remaining.

Bluiett split two free throws to give Xavier a 57-56 lead with 53.5 seconds remaining. Savage was fouled on a drive with 38.6 seconds to go but left with an injury. Baldwin shot the free throws, making one to tie it at 57.

Baldwin drained a 3-pointer with one second left in the first half as Butler took a 30-26 lead into the break.

Xavier started stronger and used a 9-0 burst to take a 13-5 lead. But the Bulldogs whittled away and a 12-3 run, culminated by five straight points from Savage, allowed them to take a 17-16 edge with 8:23 left in the half.

A 3-pointer by Bernard gave the Musketeers a 21-19 lead with 5:35 to play before Butler closed the half in solid fashion.

NOTES: Xavier junior G J.P. Macura scored eight points. He needs 20 to become the 53rd player in school history to reach 1,000 points. ... The Bulldogs' Chris Holtmann was named Big East Coast of the Year. The previous Butler coach to earn a similar honor was current Boston Celtics coach Brad Stevens (Horizon League, 2010). ... Musketeers junior G Trevon Bluiett's 23-point effort marked his 16th 20-point effort of the campaign. ... Butler won the two regular-season meetings by an average of seven points.