LOS ANGELES >> One small gesture by an official sparked a perfect storm of imperfect results for UCLA on Saturday at Kyle Field.

With less than a minute left in regulation and a chance to win the game, an official tapped center Scott Quessenberry and the center snapped the ball to an unsuspecting Josh Rosen. Rosen picked up the snap, then tried to find receiver Darren Andrews across the middle but threw an interception instead. It killed UCLA’s final attempt to avoid overtime, where the Bruins eventually lost 31-24.

In UCLA’s silent count, guard Kenny Lacy is supposed to tap Quessenberry to snap the ball. It worked flawlessly for the entire game until the most important moment.

Head coach Jim Mora said he will ask the Pac-12 about the play, saying at no other point in the game did an official touch Quessenberry, even when an official is supposed to stand over the center while teams substitute players on and off the field. It was a Pac-12 officials crew working the game led by referee Land Clark.

“It’s befuddling to me that after an entire game in the most crucial moment the official would decide that he’s going to come up now and touch our center,” Mora said.

Quessenberry said he went straight to the sideline after the play and didn’t ask the official for an explanation. The redshirt junior who was playing in his first game since 2014 took full responsibility for the snap.

“I’m not really sure what happened there, but it happened and I’ll take responsibility for it,” he said. “I need to be more dialed in to what’s going on around me and I wasn’t in that situation and it happened. We need to be better there — I need to be better there.”

Injury notes: McKinley (groin) ‘day-to-day’

Defensive end Takkarist McKinley is “day-to-day” after injuring his groin early in Saturday’s loss to Texas A&M, Mora said. An MRI on Sunday found that there was swelling, but nothing significant the coach added. McKinley was also hampered by a groin injury during training camp.

“I think we just have to make sure we make good decisions with him going forward so that this doesn’t linger all year,” Mora said.

If McKinley is out for Saturday’s game against UNLV, then the Bruins can take solace in the possible return of his replacement Deon Hollins. Mora is hopeful Hollins (concussion) can return this week. Fullback Cameron Griffin (concussion) is also expected to return to practice and could play against UNLV, if he doesn’t suffer any setbacks.

Running back Nate Starks, who did not travel with the team to College Station, Texas due to a coach’s decision, is practicing with the team this week, but his status for Saturday’s home opener will be determined at game time, Mora said.

Receiver Theo Howard was also absent from Saturday’s participation report. The freshman was expected to contribute right away to UCLA’s passing game, but remained on the sideline while some of his fellow receivers struggled catching the ball. Mora said the rotation of players just didn’t have a place for Howard on Saturday.

“You can’t get everyone in,” Mora said. “So he didn’t get in.”