Dunn scored 24 points, making all of his six 3-pointers before getting hurt with 6:43 left when Baylor already had a double-digit lead, and the Bears (No. 10 ESPN/USA Today, No. 11 AP) went on to a 68-54 victory over Arizona State on Thursday night.
While going for an offensive rebound, and being called for a foul, Dunn fell hard and was on the court writhing in pain. He went to the bench and was still rubbing his arm and grimacing when getting ready to return 2 minutes later.
"It's tender right now. It's hurting," Dunn said after the game. "I went up for the rebound and just came down wrong."
Initially, Dunn didn't ask to come back in the game, only his third this season for Baylor (6-0).
"I wasn't at first, because I couldn't feel it," he said. "After I got my arm back, I told coach I was all right. I hope it's just bruised. ... I hope it's nothing broken or fractured or anything like that."
Dunn said he will have X-rays on Friday.
Rihards Kuksiks hit consecutive 3-pointers for Arizona State (3-3) in the opening minute of the second half to tie the game at 33. Dunn responded with a 3-pointer, the first of his two in a 7-2 run that put the Bears ahead to stay.
Baylor led 59-45 when Dunn got hurt. While sitting at the scorers table waiting to return, and even when he got back on the court, he was still rubbing and shaking his arm.
"You're always concerned, but obviously Lace, especially with him just getting back to us, you don't want to see him be out for an extended period," coach Scott Drew said. "Lace is a very tough kid, and if it's not broken, he's playing."
Dunn, the leading scorer last season when Baylor made it to an NCAA regional final and had a school-record 28 wins, was suspended for the first three games of the season after violation of team rules.
In his three games since returning, Dunn has averaged 22.7 points and made 16 3-pointers. He was already Baylor's career leader for 3-pointers, and now has 315 -- with at least one in 20 consecutive games. He was 6 of 12 on 3-pointers against the Sun Devils, though he took no more long-range shots after getting hurt.
"Dunn is clearly one of the top two guards in the country," Arizona State coach Herb Sendek said. "He's a terrific player, one of the best in college basketball right now. He doesn't need a lot of time and space, and he's very accurate."
Kuksiks led Arizona State with 13 points, while Ty Abbott had 12 on four 3-pointers and Kyle Cain scored 10 points.
Soon after getting back in the game, Dunn dived on the court for a loose ball -- reaching out for a steal with his left arm that was hit by a defender.
"Lace is a soldier," Walton said. "In practice, he goes down and the next minute he's right back up shooting."
The Bears have an extended break with exams coming up next week. They don't play again until Dec. 15, against Bethune-Cookman.
Baylor hadn't trailed at all in its previous three games, and Drew called a timeout after Arizona State had a 5-0 lead only 83 seconds into the game. The Bears responded with a 16-3 run, when the only ASU basket was Abbott's 3-pointer.
After Abbott's 3 put the Sun Devils up 8-7, they had four turnovers and got off one shot over the next 4½ minutes. Jones had a dunk and another inside basket, Dunn hit a 3 and Walton had a fadeaway jumper for a 16-8 Baylor lead.
The Bears stretched the lead to 30-18 when J'mison Morgan gathered in the ball underneath the basket and made a reverse layup with just under 7 minutes left until halftime. They led 33-27 at halftime before the two fast 3s by Kuksiks.
"We came out, tied it up pretty quickly," Sendek said. "They went on another run and we couldn't volley back."