Corvallis, OR (SportsNetwork.com) - Nick Johnson finished with 25 points, six rebounds and four assists as No. 3 Arizona fended off the Oregon State Beavers 74-69 in a tight Pac-12 clash.

Rondae Hollis-Jefferson chipped in with 13 points while Kaleb Tarczewski and Gabe York each netted 12 for the Pac-12 champs (28-2, 15-2 Pac-12), who have won four straight since a double-overtime loss to Arizona State.

Roberto Nelson checked in with 25 points to lead Oregon State (15-14, 7-10), which has lost six of its last eight games.

"We can't get demoralized by this. We have to take this game, realize what it feels like and then go back and get some more. This game on Saturday has become extremely important. If we want to make a run, our tournament should start on Saturday, not next week," said OSU coach Craig Robinson.

The Beavers had the Wildcats within their sights, but four of their 16 turnovers came after Eric Moreland's tip-in evened things at 64-64 with just over five minutes to play.

Hollis-Jefferson's layup broke the tie, and Arizona pulled out a seventh straight win in the series with timely defense and an 8-for-10 effort from the free throw line over the final two minutes.

The Wildcats held the biggest lead of the game at nine, 31-22, following a Johnson dunk inside four minutes left in the opening half.

Oregon State countered with the next seven points to keep it close, as Olaf Schaftenaar knocked down a 3-pointer, Devon Collier added a tip-in and Nelson made two free throws, and the Beavers were within 36-33 at the break.

The teams traded 7-0 runs after the game was tied at 51-51, and it stayed close the rest of the way.

Game Notes

Oregon State has not beaten a top-5 team since 2000 when it upset No. 3 Arizona, 70-69, in overtime ... Nelson has 17 20-point games this season ... Arizona, which came in with a +9.2 rebounding margin, was beaten on the glass by a 40-24 margin ... Arizona closes out the regular season at Oregon on Saturday ... Oregon State hosts Arizona State Saturday.