UCLA quarterback Josh Rosen is done for the season

Reporting from Boulder, Colo. — Josh Rosen will not throw another pass for UCLA in 2016. He is out for the season, and teammate Mike Fafaul said after the Bruins’ loss to No. 15 Colorado on Thursday night that Rosen will have shoulder surgery next week.

Bruins Coach Jim Mora told a TV sideline reporter before the game that Rosen did not accompany the Bruins on their trip because of a lingering shoulder injury.

The official UCLA football Twitter feed hinted at the latest development 10 hours before kickoff when it sent out a game-day graphic featuring a Bruins quarterback with his arm cocked and ready to throw the football.

It wasn’t Rosen.

Fafaul started a third consecutive game in place of Rosen, who suffered a season-ending injury against Arizona State on Oct. 8. Mora had said Tuesday he wasn’t ruling out the possibility of Rosen’s playing again this season. But Rosen wasn’t progressing in his recovery. He short-armed a few passes during warmups Saturday, though it was unclear whether he did so as a protective measure or because he couldn’t fully extend his arm.

Rosen had an MRI exam before it was disclosed that he was finished for the season. Fafaul said Rosen would have surgery on his shoulder next week.

“He’s going to handle it like a man and I’m sure he’ll be fine,” Fafaul said.

Mora backtracked this week after previously saying Rosen had suffered a nerve issue in his shoulder, insisting there was no nerve damage. But he implied the team would be cautious before allowing Rosen to return.

“We’re going to always do what’s best for our players and their long-term care, their long-term health, their long-term well-being,” Mora said this week. “Sometimes that means protecting them from themselves.”

Rosen was knocked out of the game against Arizona State in the first half with a lower-body injury before returning, only to be sidelined again with the shoulder injury.

He was playing his best football of the season at the time he was sidelined. He had thrown for 350 yards and three touchdowns without an interception the previous week against Arizona before throwing for a career-high 400 yards and two touchdowns with one interception against the Sun Devils.

Rosen finished the season having completed 59.3% of his passes for 1,915 yards with 10 touchdowns and five interceptions. He was sacked 13 times in six games, the lack of protection resulting in the sacks on which he was injured against Arizona State.

There had been hope before the season that the addition of a fullback and tight ends to UCLA’s offense would lead to improved protection, though Rosen downplayed the impact of the changes. “Protection-wise,” Rosen said the week before the season opener, “we’ve still got the same five dudes that are busting their butts, but they’re going to do just as well as they did last year.”

Rosen has two more years of eligibility remaining but is widely expected to complete his junior season and enter the 2018 NFL draft.

Quick hits

UCLA defensive tackle Eddie Vanderdoes started as usual after being limited in practice this week because of an injured ankle. … Bruins cornerback Nate Meadors made his first appearance since hurting his groin in warmups last month against Arizona State.

UP NEXT: Oregon State, TV: Pac-12 Networks, 6 p.m. Nov. 12 at the Rose Bowl.

The Beavers have lost their two Pac-12 Conference road games, against Colorado and Washington, by a combined score of 88-23.

ben.bolch@latimes.com

Twitter: @latbbolch