PULLMAN, Wash. (AP) As Washington State held a narrow lead over Colorado midway through the second half, Charles Callison was on track for a career outing.

Then Callison hit two more 3-pointers, back-to-back. Then another. And, finally, one more, which put the Cougars up by 11, the biggest margin of the game until that point.

''After the first few,'' Callison said,'' it looked like I was throwing a rock into the ocean.''

Callison scored a career-high 30 points and had five steals, to pace Washington State past Colorado 91-89 in overtime on Saturday, as the Cougars put a four-game losing streak to rest and kept the Buffaloes winless in conference play.

Ike Iroegbu delivered the game-winner.

With the game tied at 89, he converted a contested layup on a fast break to give Washington State the lead with 10.5 seconds left in overtime after Derrick White's jumper had put Colorado up two with 1:52 left.

''We knew coming into the game it was going to be close,'' Iroegbu said. ''We knew they needed a win as bad as we needed a win, but this is our home court so we just couldn't lose.''

The Cougars led by 11 with 5:53 to go in regulation. Colorado cut the deficit to two after White converted a three-point play.

Josh Hawkinson scored on a hook shot to put the Cougars up four with 35 seconds to go in regulation. Xavier Johnson tipped in a George King miss, then White hit two free throws to tie the game at 83 with 7.2 seconds left. Callison missed a long 3 at the regulation buzzer.

White hit two foul shots to tie the game with eight seconds left to force overtime.

Iroegbu finished with 20 points and eight boards. Hawkinson had 18 and 6.

''Can't say enough about Charles just relaxing, finding himself and playing so well,'' Washington State coach Ernie Kent said. ''But I still think there's more growth potential with us. . to say we're there, nope, we still have work to do.''

White paced Colorado with 25 points, six assists and five rebounds. He also supplied the game-tying free throws in regulation and a key bucket in overtime.

''To get this game into overtime was a big-time task and we've got to credit our guys for making that happen,'' Colorado coach Tad Boyle said. ''We just can't sustain it. . that's why we're losing games. Our defense is not good enough to beat anybody in this league.''

WSU led for most of the first half, which counters its last game, a 41-point home loss to Utah, where the Cougars fell out of contention early.

Consecutive 3s from Viont'e Daniels and Malachi Flynn gave WSU a seven-point advantage late in the first and entered halftime up four.

The teams traded baskets throughout the second. The Cougars' shooting helped them maintain the lead. Colorado did not regain the lead until overtime.

BIG PICTURE

Colorado: Colorado couldn't nab its first Pac-12 win at Washington State and is winless through its first seven conference games. Three of its losses came by a margin of three or less points, most recently with an 85-83 overtime loss at Washington Thursday.

Washington State: The Cougars found their shooting stroke early and often. They shot 53.8 percent from the field, a cut above the season average (44.4 percent). WSU has been down on a winless streak of its own recently, but Saturday's win breathed some life into the Cougars' season.

UP NEXT

Colorado: The Buffaloes return home with a chance to pick up momentum as they host Oregon State on Thursday and No. 11 Oregon on Saturday.

Washington State: The Cougars head down to the desert for key road tests at No. 14 Arizona - which recently lifted the suspension of standout guard Alonzo Trier - on Thursday and Arizona State on Jan. 28.

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