SALT LAKE CITY – When Connor Mack comes off the bench, typically it's his defense that Cal head coach Mike Neu is looking for.

On Saturday, the sophomore outfielder stepped up with the bat in his hands. After Grant Holman delivered a game-tying double in the top of the eighth, Mack broke the deadlock with a two-run homer that made the difference in the Bears' 6-4 victory over Utah.

Mack's game-changing blast went to the opposite field in right, landing on the grassy berm that rings the area beyond the outfield wall at Smith's Ballpark. He rounded the bases and was greeted by a raucous reception in front of Cal's dugout.

Home run celebrations have been commonplace in this season where the Bears are among the Pac-12's best slugging teams. But seeing Mack deliver the damage wasn't so predictable.

His only other homer this season came back on Feb. 17 against Northwestern, in Cal's third game. He had gone nine games without driving in a run, but he came through huge in a win that clinched this three-game series for Cal (26-15, 12-8 Pac-12) with Sunday's series finale still awaiting.

"That was big,"  Neu said of Mack, who entered the game to pinch-run for Garret Nielsen in the sixth inning. "I thought he put a great swing on the one he fouled off (before the homer). Then he hits that one out of the park.

"I'm excited to see him do that because he's been working hard."

Cal trailed 4-3 entering the eighth when Darren Baker led off with a single to left. He moved to third on two wild pitches, and with one out, Holman drove a double to right-center to tie it.

Up stepped Mack, who fell behind in the count 1-2 against Utah right-hander Zac McCleve before going deep to the opposite field. The sophomore from San Jose began the season as Cal's starting left fielder, then missed time with a sprained ankle and has alternated with Nielsen lately in left field.

"Coming in in the late innings, usually I'm a defensive replacement in a close game," Mack said. "You've got to come in and be ready to go. You can't be tentative. That's definitely the challenge, to stay locked in."

Holman, who started the game at designated hitter, took the mound for the ninth and notched his first collegiate save. Ian Villers (2-1) was credited with the victory in relief.

Cal starter Jared Horn had a streak of four consecutive starts of at least eight innings snapped. The right-hander gave up three runs on a season-high nine hits over six innings, and he issued three walks. But he came up big in both the fifth and sixth innings to keep the Utes (12-27, 4-19) off the board in a 3-3 game.

With the bases loaded in the fifth, he coaxed a 4-6-3 double play grounder from Briley Knight to end that threat. In the sixth, Horn had the go-ahead run on third with one out and took a sharp comebacker off his throwing hand on Matt Richardson's single.

The runner at third, Chase Fernlund, had to stay put. Oliver Dunn followed with an attempted safety squeeze bunt that wound up going for a sacrifice that put runners at second and third. Horn then got Erick Migueles to chase strike three to end that rally on his 101^st and final pitch.

Sunday's series finale begins at 11 a.m. (PT) with the Bears going for their fourth sweep of the season.