LOS ANGELES — For all of Arizona's decorated basketball history, the 2013-14 Wildcats have done something none of their predecessors accomplished.

LOS ANGELES — For all of Arizona's decorated basketball history, the 2013-14 Wildcats have done something none of their predecessors accomplished.

Brandon Ashley and T.J. McConnell each scored a season-high 19 points and No. 1 Arizona beat Southern California 73-53 Sunday night to improve to 17-0 for the best start in school history.

"We're really excited about it, we really are," Arizona coach Sean Miller said. "We talked about it and it's something I think all of us will really cherish. Any school record you break at Arizona in the basketball program is a real record because of the great tradition that we have."

The 1931-32 Wildcats held the previous record for best start at 16-0.

"It feels great to know we got the record," said McConnell, who also had six assists. "But we have to move on because we have another game on Thursday."

Arizona didn't pull away and secure the record until the final minutes. The Wildcats led just 34-31 at halftime and 48-43 with nine minutes to play, but then they reeled off an 18-6 run — highlighted by eight points from McConnell — to finally put USC (9-7, 0-3 Pac-12) away.

All in all, Arizona outscored the Trojans 25-10 over the final 8:33 to turn the close game into a rout and improve to 4-0 in the conference.

"We were just trying to stay poised the last few minutes of the game and really just had a defensive mindset to really lock down," guard Nick Johnson said. "They're a good team and we knew that coming in. They gave us their best shot and they had us for a little bit, but we rallied back and stayed with it."

Johnson chipped in 15 points and Aaron Gordon had 12 for the Wildcats, the second straight game they've had four players reach double figures in scoring.

Washington St. 49, Utah 46

At Pullman, Wash., Que Johnson had 14 points and went 10 of 13 from the free throw line to help Washington State beat Utah.

The Cougars (8-8, 1-3 Pac-12) came back from a 12 point deficit for their first Pac-12 win.

With 56 seconds on the clock, Delon Wright stole the ball from Johnson and went the length of the court for a dunk to pull the Utes within one, 47-46.

After an offensive foul on Johnson, Utah's Brandon Taylor traveled and put the ball back in the hands of Washington State.

The Utes (12-4, 1-3) were forced to foul and Johnson made a pair of free throws. Washington State fouled Delon Wright on the next play, but he missed both free throws. Wright had one more look at a three but missed short as time expired.

Washington 71, No. 15 Colorado 54

At Seattle, C.J. Wilcox set career highs with seven 3-pointers and 31 points, including 21 in the second half, and Washington ran away from No. 15 Colorado.

It was Washington's first win over a ranked team since Isaiah Thomas' jumper beat then-No. 16 Arizona in the 2011 Pac-10 Conference tournament championship game. Washington (11-6, 3-1 Pac-12) had lost 12 straight against ranked teams.

Colorado (14-3, 3-1) never recovered after leading scorer Spencer Dinwiddie crumbled to the court late in the first half after his left knee buckled while dribbling on a fast break. Dinwiddie had to be helped to the locker room by teammates and did not return.

The Huskies outscored the Buffaloes 49-29 after Dinwiddie's injury.

UCLA 87, Arizona St. 72

At Los Angeles, Kyle Anderson scored 17 points and pulled down 13 rebounds while leading UCLA to victory.

Anderson recorded his 9th double-double of the season as the Bruins (13-3, 2-1 Pac 12) beat the Sun Devils (13-4, 2-2) for the 7th time in their last 8 games.

Jordan Adams scored 15 points, Bryce Alford added 13 and Norman Powell scored 11 points for the Bruins.

UCLA 14-0 run to take a 20-12 lead following a 3-pointer by Zach LaVine with 12:11 remaining in the opening half.