Trailing by nine inside the final minute of the first half, arguably the most exciting moment for the Bruins to that point was actually a low point when head coach Mick Cronin disagreed with a blocking foul, tossed aside his jacket over the bench and picked up a technical foul as he let two officials know what he thought about the call.

The rest of the Bruins' early frustrations Saturday evening centered around being beat for offensive rebounds, carelessly turning the ball over and the ongoing struggles with their offense.

UCLA never recovered, never even led against a California team that came in winless through its first three Pac-12 games, and lost 66-57 at Pauley Pavilion.

The Bruins (6-9, 1-3 Pac-12), who have lost four consecutive home games since having the previous longest home winning streak snapped more than two weeks ago, were out-rebounded 39-29 — including 14-6 on the offensive boards.

It was the first time UCLA has lost four consecutive games at Pauley Pavilion since 2003.

The loss was enough to keep Cronin and players from addressing the media, leaving Bruins assistant coach Rod Palmer to answer questions.

“Physicality. That’s what it comes down to,” Palmer said. “Either you’re going to hit someone or you’re going to get hit, and we’ve been getting hit a lot. When you get hit a lot, it ends up a minus-10 in rebounds.

“We don’t have a margin for error. So if we turn the ball over and get out-rebounded, that’s going to limit our chances even more. So, you know, we have to stop doing those things first of all. Coach is trying to put the ball in people’s hands to score, guys who can score, and a lot of times they just think it’s for them to score when in actuality it’s for them to score if they can, but find the open guy if they can’t. And that’s the disconnect right there. So we just have to stress using each other, sharing the ball with each other and hopefully things will get better.”

Freshman guard Sebastian Mack scored 18 of his team-high 20 points in the second half to pace UCLA, which made just 9 of 25 shots in the opening half and trailed 32-23 through the first 20 minutes,

Cal (5-10, 1-3 Pac-12), which won at Pauley Pavilion for the first time since 2010, was led by Jaylon Tyson's 22 points on 9-of-12 shooting.

The Golden Bears made of 8 of 20 3-pointers en route to the victory. The Bruins were just 2 of 10 from beyond the arc.

The Bruins will next travel Thursday to Utah for a 6 p.m. PT contest that will air on ESPN2.

The game essentially came down to the first half, with UCLA unable to cut the deficit below seven points until an Adem Bona fastbreak layup pulled the Bruins within 61-55 with 1:44 to play.

The Golden Bears answered with a Jalen Cone 3-pointer on the next possession and the Bruins never drew any closer.

The freshman was the lone UCLA player with more than five shot attempts to shot better than 50% from the field.

Mack made 7 of 13 shots and 5 of 6 free throws despite a mostly ineffective nine first-half minutes.

On most nights Bona blocks two shots and collects four steals, this space would be reserved for him. However, three rebounds, including just one on the defensive glass, contributed more to UCLA's woes than the other numbers.

Mack, meanwhile, had two of his three steals in the second half and was the more effective player on the night.

Honorable mention goes to reserve guards Will McClendon and Ilane Fibleuil, who had identical rebounding numbers with five of their six boards apiece on the defensive glass.

After failing to produce any transition points in the loss to Stanford, UCLA provided a flashback of sorts to last season when Bona blocks regularly turned into fastbreak baskets.

On this particular sequence in the first half, it was Mack on the finishing end:

The rebounding issues compounded the already inept offensive issues.

The Bruins were also outscored 15-14 in points off turnovers, 12-9 in second-chance points and failed to take advantage of finally getting transition baskets.

UCLA's lone bright spot was a 10-0 edge in points on the break.