TUCSON, Ariz. –  Derrick Williams had 15 points and 12 rebounds, Lamont Jones added 17 points and No. 18 Arizona earned a share of its first Pac-10 title in six years with a 70-59 win over Oregon State on Thursday night.

Coming off consecutive losses for the first time this season, Arizona (24-6, 13-4 Pac-10) overcame some early shooting woes with defensive pressure, then pulled away in the second half to move within a game of its first undefeated home season in 12 years.

The Wildcats had an efficient night offensively with 17 assists and eight turnovers, then earned a share of the conference title when UCLA lost to Washington. Arizona can win the title outright by beating Oregon at home on Saturday.

Oregon State (10-18, 5-12) shot well (50 percent), but had 22 turnovers and was worn down by Arizona's depth while losing its 10th straight on the road. Devon Collier led the Beavers with 12 points.

Arizona needed a pick-me-up after its trip to SoCal went awry.

Hoping to lock up the Pac-10 title, the Wildcats instead floundered against Southern California and UCLA, making the final two home games a lot more important than they had hoped.

The conference's second-best scoring team, Arizona averaged a meager 53 points in the two losses — 23 points below its season average — and wasn't particularly good defensively, at least inside the arc.

Williams all but disappeared in the loss to the Trojans, scoring eight points on 3-of-11 shooting, and the Bruins reeled off a 26-4 run spanning halftime to send the Wildcats to their worst loss of the season.

Williams was back to looking like a national player of the year candidate in the first half against Oregon State, skying for rebounds, alternately slicing and powering his way through the lane.

Wearing a pink bandage on his injured right pinky instead of the usual white, the sophomore forward had 13 points on 5-of-8 shooting and 11 rebounds at the half, helping Arizona to a 34-23 lead.

Oregon State has been near the bottom of the Pac-10 most of the season, but sure has given Arizona problems the past two years.

The Beavers swept the Wildcats last year, including their first win in Tucson in 27 years, and held off Arizona by one at Corvallis in early January after forcing 19 turnovers and grabbing 12 offensive rebounds.

Oregon State's secret: Its 1-3-1 zone.

Well, that's at least part of it.

Arizona had no answer for the defense last season and even though the Beavers don't use it as much this year, the Wildcats figured it'd be a big part of their repertoire in the desert.

Oregon State did indeed break out the 1-3-1 and Arizona had more trouble with it, missing its first nine 3-point shots. The Wildcats made up for it with defense, forcing eight turnovers in the first eight minutes and 14 total in a mostly ugly first half by both teams.

Oregon State made a brief run early in the second to cut Arizona's lead to six and was able to hang around by limiting Williams' touches. The rest of the Wildcats made up for it, though, with Kyle Fogg and Jones hitting 3-pointers on consecutive trips to make it 56-43.