UCLA QB Josh Rosen does not make trip to Utah; Devon Modster makes his first start

Scanning the field in hopes of spotting quarterback Josh Rosen somewhere, anywhere, during UCLA’s game against Utah on Friday night proved to be a pointless exercise.

Rosen remained home in Los Angeles because of a concussion, leaving redshirt freshman Devon Modster to make his first career start at quarterback for the Bruins at Rice-Eccles Stadium.

Rosen sustained the concussion against Washington last weekend during a game in which he was sacked four times in the first half. He left midway through the third quarter and did not return.

Rosen was shown with a cut on his left (non-throwing) hand during the game broadcast and afterward UCLA coach Jim Mora said that Rosen had suffered “multiple” injuries.

It remained unclear how long Rosen might be out or whether he could return Nov. 11 when the Bruins play host to Arizona State at the Rose Bowl in their next game. Rosen leads the Pac-12 Conference in passing yards (2,713), passing yards per game (339.1) and total offense (333.9 yards).

Rosen missed the final six games of UCLA’s season in 2016 with a shoulder injury and the Bruins went 1-5 with former walk-on Mike Fafaul filling in at quarterback.

Modster brings more impressive credentials. Considered one of the nation’s top dual-threat quarterbacks coming out of Tesoro High in Rancho Santa Margarita, Modster completed seven of 12 passes for 77 yards and a touchdown against Washington in the first extended action of his career.

Accruing additional playing time could help Modster in the battle to become Rosen’s successor should Rosen leave for the NFL draft after this season. Dorian Thompson-Robinson, another highly touted dual-threat quarterback who is a senior at Bishop Gorman High in Las Vegas, has committed to UCLA for next season.

Thompson-Robinson said last month during an interview with The Times that he wanted to play as soon as possible.

“I definitely want to go in there and just get on the field right away,” Thompson-Robinson said.

Receiver Jordan Lasley missed a third consecutive game because of a disciplinary issue, depriving the Bruins of one of their most explosive players.

Mora has not said when Lasley might be able to return, only that his status would be evaluated on a week-to-week basis.

Tailback Jalen Starks returned from the ankle injury that had sidelined him since the game against Arizona on Oct. 14 and defensive end Rick Wade played some on special teams in his first game since injuring his knee against the Wildcats.

Tight end Austin Roberts, who injured his ankle against Oregon on Oct. 21, warmed up but did not play, with Jordan Wilson getting the start in his place.

Defensive lineman Ainuu Taua was hurt on a kickoff return late in the second quarter and had to be helped off the field.

UCLA receiver Darren Andrews’ first catch against Utah, on the Bruins’ opening drive, moved him into sole possession of fourth place on the school’s all-time receptions list. Andrews entered the game in a fourth-place tie with Danny Farmer, who caught 159 passes from 1996-99.

Andrews, however, appeared to suffer a right knee injury early in the fourth quarter after planting his leg awkwardly.

Andrews finished the game with three catches for 66 yards and needs 17 more catches to tie Kevin Jordan for third place. Jordan caught 179 passes from 1992-95. Only Craig Bragg (193 catches) and Jordan Payton (201) have more catches than Jordan in UCLA history.

ben.bolch@latimes.com

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