Putting more faith in quarterback Josh Rosen might benefit conservative Bruins

UCLA doesn’t have a football game this week, and maybe the Bruins can use the time to mull over the idea of loosening the grips on quarterback Josh Rosen.

UCLA’s play-calling has become increasing conservative, particularly on first down. Arizona State loaded up defenders at the line of scrimmage Saturday and the strategy worked. The Bruins were held to 62 yards rushing in a 38-23 loss.

That ended a streak of 24 games in which UCLA ran for at least 100 yards and was the Bruins’ lowest total since 2012, when they ran for 33 yards against Baylor in the Holiday Bowl.

In their first 19 first-down plays, UCLA ran the ball 11 times and fell behind, 29-10.

“They were kicking our butts,” offensive coordinator Noel Mazzone said.

Asked why the Bruins kept trying to run, he added, “I’m stubborn sometimes.”

Mazzone also noted that when UCLA is able to establish the run it takes pressure off its freshman quarterback.

Against Arizona State, it didn’t happen.

Paul Perkins, who entered the game as the nation’s 10th-leading rusher, finished with 63 yards, averaging 3.5 yards per carry.

“ASU did a really good job of bringing a lot of exotic pressures,” Perkins said. “That’s what kind of tripped us up.”

UCLA passed more often than not on first down early in the season. Against Virginia, the Bruins passed on first down 10 times and ran four times. Against Nevada Las Vegas, they passed 12 times and ran seven times on first down.

But in the first half of its last three games, UCLA ran the ball 44 times on first down and passed it 19.

“We pride ourselves on running the ball,” receiver Thomas Duarte said. “We have the experience up front on the line. We have experience in Paul, and we believe in him.”

The Sun Devils beat UCLA at simple math. There were more defenders on the line than blockers.

“They had some guys strictly for the run who we didn’t think would be strictly for the run,” Duarte said. “They were intent on not letting Paul run the ball.”

Asked what could be done to counter that, Duarte said, “You throw the ball. You work around it. You work your reads.”

When the Bruins turned to passing in the third quarter, Rosen engineered consecutive touchdown drives to get UCLA back in the game.

Rosen suffered from several dropped passes but still completed 22 of 40 for 280 yards and two touchdowns.

That’s a fact (about) Jack

Injuries, particularly to linebacker Myles Jack, have affected the Bruins’ defensive performance the last two games.

Arizona ran for 353 yards against the Bruins, Arizona State 192.

“The approach has to change a little bit in terms of mindset,” linebacker Deon Hollins said. “You have to be in more of an attack mindset. Small mistakes you could make earlier won’t fly now.

“Earlier in the year, if they happened to get past Kenny [Clark], Eddie [Vanderdoes] or me, we had the best player in the nation on clean-up duty.”

Ticked off

The Bruins defense was on the field for 37 minutes 47 seconds against Arizona State. The Sun Devils ran for 134 yards in the second half.

Hollins said fatigue was not a factor.

“Guys got out of gaps,” he said. “I don’t want to say it was fatigue. It was just a little lazy play by us.”

UCLA can expect Stanford to attempt to control the tempo Oct.15. On Saturday, the Cardinal held the ball for 37:19 in a 55-17 victory over Arizona.

“This is where we separate Jimmys from the Joes,” Hollins said. “We’re coming to the point of the season where all the work you did in summer and spring is something you draw on. This is going to be really important.”

Chris.foster@latimes.com

Twitter: @cfosterlatimes