While the Wildcats have continued their winning ways, the Golden Bears have not.
Arizona can become the fifth team in the last 10 seasons to open with 22 victories as it looks to hand California a fourth straight defeat Saturday night in Berkeley.
Both teams began 5-0 in conference play, and Arizona coach Sean Miller referred to California this week as "right there, competing for the Pac-12 championship."
The Golden Bears (14-7, 5-3) fell three games off the pace with Wednesday's 89-78 overtime loss to Arizona State that ended their 10-0 home start.
"We have to win," said top scorer Justin Cobbs about Saturday's game. "We can't keep losing games at home. We've dropped three straight so we have to perform, we have to win."
That same night, Arizona (21-0, 8-0) survived a scare with a 60-57 victory at Stanford. The Wildcats overcame season-low 36.0 percent shooting and 11 missed free throws by limiting the Cardinal to 37.5 percent from the field.
''We're an outstanding defensive team," Miller said. "It isn't as if we changed any scheme, we just buckled down and had a lot of players playing very hard, and our ability to hold them to what we did is a big reason we won. Our defense won the game tonight.''
Arizona is among the nation's best defensive teams, allowing 56.7 points per game and 37.2 percent shooting to rank first in the conference in those categories.
The Wildcats were also held to 40.0 percent shooting in Sunday's 65-56 win over Utah, and know they must be better offensively.
''No question we have to execute better on offense and we have to be more confident at the line," Miller said. "We'll work toward that as we approach Saturday.''
A sold-out, raucous crowd awaits the Wildcats at Haas Pavilion. It was a similar scene Wednesday, when Nick Johnson scored a game-high 16 points.
"We know by now that we're going to get everybody's best shot, and that's what happened," Johnson said. "Packed crowd, a hyped crowd tonight - it was a tough game."
California is facing a less-than-ideal opponent to try to break out of some shooting woes. The Golden Bears are shooting 40.5 percent during this slide, including 25.5 percent on 3-pointers.
Coach Mike Montgomery's club made 4 of 13 from long range (30.8 percent) against the Sun Devils.
"They were packing the paint and daring us to shoot the 3," Montgomery said. "One of the things we're struggling with right now is we're not shooting the ball very well. We've just got to keep working."
Cobbs scored 21 - the same amount he finished with in last season's lone meeting, a 77-69 win at then-No. 7 Arizona on Feb. 10.
The Wildcats have won by a total of six points in their last two visits to Berkeley.
Northern California natives Brandon Ashley and Aaron Gordon will try to fare better Saturday after they combined for 15 points on 5-of-19 shooting against the Cardinal.