INDIANAPOLIS -- It was tale of two halves for both Butler and freshman Kamar Baldwin.

The freshman guard scored all of his career-high 21 points in the second half to lead the No. 12 Bulldogs to an 83-78 victory over No. 15 Xavier in a Big East Conference game on Saturday at Hinkle Fieldhouse.

Baldwin stole a pass in the final two seconds to keep Xavier from getting a shot at a potential game-tying 3-pointer and then hit two free throws to seal it with less than one second left. After trailing Xavier 31-25 at halftime, Butler (15-3, 4-2 Big East) outscored the Musketeers (13-4, 3-2) 58-47 in the second half.

"Kamar made a lot of important plays for us on both ends," Butler coach Chris Holtmann said. "What I've said about Kamar from Day 1 is he is able to impact the game on both ends. It's hard to get him out of the lineup."

Baldwin, who sank 6 of 11 shots and all eight free throws, delivered a team-high nine rebounds.

"It was pretty much taking what the defense gave me," Baldwin said. "I was able to make open shots."

Butler opened the second half with eight unanswered points to take a 34-31 lead. J.P. Macura sank a 3-pointer to tie it at 34-34. Butler grabbed the lead for good at 38-37 but it wasn't easy.

"They came out in the second half and punched us in the mouth," Xavier guard Malcolm Bernard said.

Musketeers coach Chris Mack echoed that view.

"Butler really took it to us in the second half, they had their way getting down the lane," Mack said. "Then we could not stop them without fouling them."

In a foul fest, the Bulldogs sank 33 of 38 free throws while the Musketeers were 28 of 39 from the foul line.

"I have the utmost confidence in our guys in these late-game situations, and they stepped up and made free throws," Holtmann said.

Trailing 72-66, Xavier got back in it with one big sequence. Edmond Sumner scored and failed to convert on a three-point play, but Xavier got the rebound and Macura sank a 3-pointer to cut the lead to 72-69 with 2:06 left.

Bernard hit a 3-pointer with 37 seconds to trim the lead to 73-72. Andrew Chrabascz, who had 16 points, was fouled and hit both free throws for Butler with 18.5 seconds left. Sumner answered on a layup with 12 seconds left.

Kelan Martin followed with two free throws with 10.8 seconds left to put Butler ahead by three. Two free throws by Sumner cut it the deficit to 77-76.

With 7.5 seconds left, Baldwin hit both free throws to make it 79-76, and four seconds later Myles Davis of Xavier sank both free throws to slice the lead to one again.

Martin made two free throws with 2.9 seconds left to push the lead to 81-78 and the Bulldogs held on.

"I thought our guys make really big plays down the stretch to beat a really good Xavier team," Holtmann said.

Sumner was high for Xavier with 22 points and Macura fouled out with 16 points.

Chrabascz gave Butler its first lead at 20-18 with 7:10 left in the first half. The Musketeers followed with an 11-0 run to grab a 29-20 edge.

Savage broke the Bulldogs' scoring drought on two free throws with 2:32 remaining.

Martin, who struggled with his shooting in the previous five games, didn't start for the second time this season. Although plagued with foul trouble, Martin finished with 13 points.

Xavier had won six of the previous seven games against Butler in Big East play

"I think last year we pressed too much," Holtmann said. "So we weren't downplaying this game, but we also weren't treating it like the Super Bowl.'

Both teams are back in action Monday. Butler will host Marquette at noon while No. 8 Creighton is at Xavier at 2 p.m.

NOTES: Butler has won 13 consecutive games at home, including 10 this season. The Bulldogs are 10-0 at Hinkle Fieldhouse this season and have a 13-game winning streak. ... Xavier associate head coach Travis Steele is a 2004 Butler graduate. ... Xavier junior guard Trevon Bluiett played at Park Tudor High School, four miles from the Butler campus. Bluiett, who topped the 1,000-point mark on Nov. 20, is 81 points shy of cracking the school's top 25 in scoring.