"He's the kind of player they rely on to do that," he said. "They put him in there to turn up the tempo and turn up the intensity and everybody feeds off that. Everybody needs a player like that."

Gutierrez's impact served to point out that the Cardinal lack such a player.

Certainly Jeremy Green supplied an offensive boost as the Cardinal's sixth man on Saturday, making all three of his three-point attempts in the first half to help the Cardinal build on their early lead.

But the Cardinal do not have a player who can inject energy and intensity into the team when things are not going well. When things start going awry, they seldom have been able to turn the momentum back in their favor.

And things are not going well for Stanford now. The Cardinal (15-8, 4-8 Pac-10) must win all six of their remaining regular-season games to finish with a winning conference record for the 16th consecutive season. With losses in five of their past six conference games, such a winning streak will be difficult for the Cardinal, who have yet to put together a series of good performances.

"It's sort of hit and miss with us," Stanford junior Landry Fields said.

The Cardinal have lost all five of their conference road games, and they led by seven points or more in the second half of four of them. The worst collapse came Saturday, when the Cardinal lost after leading by 22 points in the first half and by 14 at halftime.

When Cal started eating into Stanford's huge lead, the Cardinal seemed to have no way to reverse the surge.

"We had that game under control," Fields said, "and they just took it. It was like they decided, 'That's ours, we're going to take it.' "

Cal took it by getting six offensive rebounds in the first six minutes of the second half, scoring eight of its first 18 points in the half on second-chance opportunities. The Bears, who used a small lineup nearly the entire second half, had 14 offensive rebounds to Stanford's five.

"Rebounding is just a matter of will and heart," Fields said. "We were just being soft out there."

The Cardinal started the game well enough, running free against the Bears' starting five at the outset, hitting 13 of their first 17 shots.

"They weren't guarding us like they were in the second half, when they were basically coming up into us," Hill said.

With Gutierrez leading the Bears' increased defensive pressure, the Cardinal missed their first six shots of the second half and never regained the offensive rhythm they had in the first half.

Anthony Goods had 10 points on 4-for-5 shooting in the first half, but was 0-for-5 with just three points in the second half when Gutierrez was his primary defender. Gutierrez was also responsible for many of Mitch Johnson's six turnovers, five of which came in the second half.

E-mail Jake Curtis at jcurtis@sfchronicle.com.

This article appeared on page C - 5 of the San Francisco Chronicle