The Wildcats scored one run in the eighth and two in the ninth, but left the bases loaded with the go-ahead run at the plate.
The loss snaps Arizona’s four-game winning streak. The Wildcats are 17-15 overall and 5-8 in the Pac-12.
“We just ran out of bullets,” said UA coach Jay Johnson.
Cal struck first off Arizona starter Randy Labaut with a third-inning RBI double by catcher Korey Lee.
Arizona answered the next inning when second baseman Justin Wylie hit a two-run homer to straight-away center, his first long ball as a Wildcat.
Cal immediately responded with a two-run triple to take the lead, which Arizona matched in the fifth with an RBI single from Austin Wells to tie the game.
The back-and-forth affair continued into the sixth and seventh inning. Cal’s Quentin Selma hit an RBI double, and Arizona matched an inning and a half later with a Nick Quintana RBI single.
Cal took the lead a fourth and final time in the eighth from an RBI single by first baseman Andrew Vaughn. Vaughn was intentionally walked three times in the ball game to go along with his RBI single.
Lee added hit a three-run home run to center field and designated hitter Grant Holman hit a two-run double to make the score 10-4.
Labaut got a no-decision. In five innings, he allowed four runs on six hits and four walks.
Reliever Vance Vannelle threw 2.1 innings, allowing the go-ahead single and three-run shot in the eighth. Johnson didn’t regret inserting him into the game.
“I think he’s had four or five quality outings in a row, and we haven’t had anyone do that,” he said. “Tie game, at home, he’s our guy.”
Cameron Haskell came in to relieve Vannelle but allowed two more runs. Nate Brown tossed a scoreless ninth.
Matthew Dyer and Brandon Boissiere both had three hits. Wells and Donta Williams each kept their on-base streak alive. Wells’ now sits at 26, while Williams’ is at 23.
Quintana flashed defensively. He had two great picks of ground balls, with one saving a couple of runs.
Cameron Cannon was forced to play shortstop as Jacob Blas and Dayton Dooney were out with injuries.
Arizona will look to get back to winning ways Saturday when it faces Cal in game two at Hi Corbett at 6 p.m. MST.