The Associated Press

TUCSON, Ariz. - The fourth-ranked Arizona Wildcats won their Fiesta Bowl Classic for the 17th time in 18 tries, but again lost Luke Walton.

Walton re-injured his right ankle when he stepped on teammate Jason Gardner's foot, and hopped off the court with 9:44 to play in Arizona's 85-71 victory over Boston University on Monday night.

Walton almost certainly will miss the Wildcats' Pac-10 opener at No. 9 Oregon Thursday.

"We won't know until tomorrow, but my guess is it will be difficult for him to be ready to play this week," Arizona coach Lute Olson said.

Walton sprained the ankle for the fourth time this season. He had just returned in Saturday's tournament opener after missing two games with the injury.

The preseason All-American forward scored 13 of his 16 points in the first 8:20 of the second half, but as he turned to head downcourt after Matt Turner's 3-pointer cut the Wildcats' lead to 66-61, Walton stepped on Gardner's foot.

As the capacity crowd fell silent, Walton pounded his fist on the court in a rare show of emotion.

"It seems like everything that has happened with him has been bad luck," Olson said. "It's not like there was a collision. It's a shame for him. It hurts us. When a guy is a fifth-year senior and this is a key year for him, he has just not been healthy."

Freshman Hassan Adams scored 17 points on 7-for-9 shooting for Arizona (7-1) and was chosen the tournament MVP. Salim Stoudamire added 12 points, including 3-of-5 3-pointers. Gardner had 11 points and six assists.

"When one person goes down, we all have to rise," Adams said. "We have played a couple games without him. I hope for the best. Hopefully, he comes back at 100 percent."

Billy Collins and Jason Grochowalski scored 13 apiece for Boston University (5-6). Turner added 11 points.

Arizona had struggled against the Terriers all night, but turned up the defensive pressure after Walton went down and went on a decisive 16-3 run.

Stoudamire sank two 3-pointers and Adams scored six in the outburst. Adams' inside move for a short jumper capped the run and put Arizona up 82-65 with 4:07 remaining.

The Wildcats credited the intense defense of freshman Chris Rodgers for igniting the big run.

"We had intensity tonight for about three minutes out of 40," Arizona's Rick Anderson said, "and that was when Chris Rodgers was in there."

Terriers coach Dennis Wolff praised his team for playing tough against long odds in a difficult environment

"I told our guys that I've been coaching for years, and I have never been more proud of a team losing a game than this game," Wolff said. "I felt like we competed hard but lost the game in the last five or six minutes. Our team wasn't put off by the atmosphere. That was good for us. We really kept our composure."

In the first half, Walton shot 0-for-4 and 3-for-7 from the foul line as Arizona sputtered to a 44-38 lead at the break.

But Walton came out strong in the second half, scoring 11 of Arizona's first 13 points. Still, the Terriers stayed close. Walton's last basket, a 10-foot jumper, put Arizona ahead 66-56. But Collins scored on a drive, then Turner sank the 3-pointer when Walton went down and it was 66-61.

Gardner missed two free throws and Channing Frye missed one of two, and the Wildcats seemed in trouble. But Boston turned the ball over, and Collins was called for an intentional foul on Adams. Adams sank both free throws, then Stoudamire sank a 3-pointer and the Wildcats were off and running.

Adams' 3-pointer, followed by his inside basket on a lob pass, started an 11-2 run that put Arizona up 25-17 on Will Bynum's inside basket with 5:53 to play in the first half.

But Shaun Wynn scored twice and Collins sank two of three free throws after Andre Iguodala fouled him on a 3-pointer in a 6-0 spurt that cut the lead to 25-23.

Rick Anderson's 3-pointer from the top of the key with eight seconds left gave the Wildcats a 44-38 lead at the break.