Southern California is a great place for retirees.

On Saturday, it was heaven for one un-retiree.

Utah senior running back Joe Williams ran for a school-record 332 yards and four touchdowns two weeks after returning to the team as No. 19 Utah kept pace in the Pac-12 South with a 52-45 victory over UCLA at the Rose Bowl in Pasadena, Calif.

Williams scored on runs of 3, 43, 64 and 55 yards as Utah (7-1, 4-1 Pac-12) stayed tied with Colorado atop the South Division.

"Yeah, I'm pretty sure they're tired of seeing the back of my jersey running down the field," Williams said of UCLA.

Williams retired because of injuries after starting the first two games of the season, but when injuries further ravaged Utah's tailback position, coaches convinced Williams to come back. He ran 34 times for 179 yards against Oregon State last week.

A rejuvenated Williams carried 29 times Saturday, and his single-game rushing total ranks as fourth-best in conference history and the most against the Bruins.

"Can't say enough about that young man and what he has meant to our team the last two weeks," Utah coach Kyle Whittingham said.

"What a blessing it is for us to have him back, and how unselfish it was for him to come back. It was legitimate. When he stepped away, he was hurting."

UCLA (3-5, 1-4) lost its third consecutive game and fourth in the past five.

"We got on the wrong side of some blocks and that young man had a great day, had a world-class day," Bruins coach Jim Mora said of Williams. "That's disappointing because we had been playing the run so well. We were searching for answers."

Williams' final touchdown put the Utes up 52-38 with 10:28 remaining.

UCLA redshirt senior quarterback Mike Fafaul, making his second consecutive start for injured Josh Rosen, attempted a school-record 70 passes as the Bruins largely abandoned a struggling ground game. His 13-yard touchdown pass to tight end Austin Roberts brought UCLA within 52-45 with 4:38 left.

The Bruins had a final possession, taking over at their 14 with 40 seconds left and no timeouts, but made little headway before the clock ran out.

Fafaul completed 40 passes for 476 yards, including five for touchdowns -- two to tight end Nate Iese. Fafaul also was intercepted four times -- twice by safety Jordan Fogal, who made his first career start because of an injury to safety Marcus Williams.

"I think Mike is gritty as heck," Mora said. "His teammates have tremendous, tremendous respect for him."

It was a wild game from the start as Utah's Cory Butler-Byrd returned the opening kickoff 99 yards for a touchdown. The Utes went up 14-0 after their first offensive possession, but UCLA stormed back.

Bruins running back Bolu Olorunfunmi, making his first career start, caught an 11-yard touchdown pass and ran for a 7-yard score to cap a 21-point blitz in a 5:09 span of the first quarter. His second touchdown came after UCLA defensive lineman Takkarist McKinley sacked Utah's Troy Williams and ripped the ball out off his hands at the Utah 14.

McKinley had a monster game with five tackles for loss, three sacks, two forced fumbles and two pass break-ups.

UCLA ran for 46 yards and has 88 on the ground in the past three games.

The Bruins are off next week in advance of a Thursday night game at Colorado on Nov. 3.

"We're not doing well enough, but it's not for a lack of effort on the part of our players," Mora said. "The key for these young men is they hang together and support each other and continue to search for answers -- absorb the disappointment but not let it affect them."

Utah moves on for a huge game Saturday at unbeaten and No. 5 Washington.

NOTES: Utah RB Joe Williams shattered the school single-game rushing record, which was 254 by Mike Anderson versus Fresno State in 1999. Williams was 34 yards short of the Pac-12 record of 366 yards set by Arizona's Ka'Deem Carey in 2012. ... Utah played without 2015 first-team all-conference S Marcus Williams and LB Sunia Tauteoli, who left last week's game with undisclosed injuries. ... UCLA QB Mike Fafaul attempted 37 passes in the first half, the second-most in the country this season for a half. Cal's Davis Webb threw 43 passes in a half against San Diego State. ... UCLA had held six consecutive opponents to fewer than 400 yards, but Utah reached that level in the final minute of the third quarter on RB Joe Williams' 64-yard touchdown run. ... Utah is 3-3 versus UCLA as a member of the Pac-12. ... UCLA has a 13-9 record against ranked teams under coach Jim Mora, but is 0-2 this season.