Austin went just 3 of 8 from the field but was 12 of 12 from the charity stripe. Kelly was 8-of-11 shooting.
Matt Bradley scored 11 points for California (11-15, 5-8 Pac-12), which snapped a four-game losing streak with its first Pac-12 road victory of the season.
"I thought Paris Austin was outstanding. He has given us great leadership up to this point and he played very determined today," said California coach Mark Fox. “For this team, no one gave them a chance to have much success so any time that they have some I want them to enjoy it and understand how they found that success so they can build on it.
"Hopefully tonight they can enjoy this victory and look back and see why we won the game so it can happen again.”
Washington State (14-13, 5-9 Pac 12) struggled to find good looks at the basket without starting point guard Isaac Bonton, who suffered a leg injury in the Cougars 86-83 overtime loss against UCLA last week.
After shooting 29% in their last matchup against USC without Bonton, including 2 of 26 from 3-point range, Washington State shot 30% against the Golden Bears, going 5 of 23 from beyond the arc. Leading scorer CJ Elleby, who averages 18.7 points per game, was held to 13 points on 4 of 18 shooting. Tony Miller led the way for the Cougars with 18 points.
Washington State has now lost three in a row for the first time this season.
"We are feeling down a little bit to be honest," said Washington State coach Kyle Smith. “I thought we would come home and have a little spark but like I said our roles have changed without Isaac and sometimes you are just uneasy with each other in different roles. I try to do what I can to make it a little easier on them but it is a challenge. I'm proud of these guys. They battled but we put ourselves into to big of a hole and that hurts.”
The Golden Bears jumped out to an 30-13 lead late in the first half as the Cougars struggled to make a basket, shooting just 27% from the field including 1 of 11 from 3-point range. At the break California was up 32-20.
The Cougars cut the Golden Bear lead to 60-54 with under two minutes to play after Miller scored a quick seven points, however, it was to little to late. Austin made six shots from the free throw line to close out the Cougars.
“It is hard to reinvent your team this late in the season so our defense probably had an advantage because of the injury to Bonton,” Fox said. “But we started the game well defensively, I thought we were unselfish throughout the game and then I thought we finished the game well.”
California: This is Cal;s first two-game regular-season sweep of the Cougars since 2013-14. ... With the win, California matched its Pac-12 win total from the previous two seasons combined. The Golden Bears won two league games two seasons ago, three last year.
Washington State: The Cougars continue to struggle making baskets without Bonton in the lineup and have now lost three in a row for the first time this season. Smith said he is hopeful Bonton will return for the Stanford matchup this weekend.
California: The Golden Bears play at Washington on Saturday.
Washington State: The Cougars host Stanford on Sunday
More AP college basketball: https://apnews.com/Collegebasketball and https://twitter.com/AP-Top25
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