Sophomore quarterback Josh Rosen threw for 307 yards and two touchdowns to help UCLA overcome a sluggish offensive start and beat BYU 17-14 on Saturday night in Provo, Utah.

Rosen got a big assist from the UCLA defense, which stymied BYU for the bulk of four quarters. The Bruins (2-1) held the Cougars to 273 total yards -- including just 23 rushing yards -- and forced nine punts.

BYU senior quarterback Taysom Hill struggled for much of the game. Hill threw for 250 yards and a touchdown.

BYU (1-2) lost a home opener for the first time since 2011 when it fell to Utah 54-10.

Neither team could get going on offense during the first quarter. BYU and UCLA combined for 124 total yards and six first downs in the quarter.

The Bruins found a little life early in the second quarter. Rosen connected with Cameron Griffin on a 6-yard pass to put UCLA up 7-0.

Then the Bruins extended their lead to 10-0 on a 24-yard field goal from JJ Molson. Adarius Pickett set up the field goal when he dived for a tipped ball and corralled an interception at the BYU 39-yard line.

BYU could not find an answer. The offense stalled throughout the first half, generating just 88 passing yards and minus-9 rushing yards and only four first downs.

UCLA stepped on the gas pedal in the third quarter. The Bruins took a 17-0 lead after converting three straight third downs -- culminating in a 33-yard touchdown pass from Rosen to Darren Andrews.

BYU's offense showed a little life on the ensuing drive. The Cougars drove 75 yards -- aided by three UCLA penalties -- and got on the board on a 1-yard run from Jamaal Williams with 3:07 left in the third quarter.

BYU didn't add a second touchdown until Hill found Nick Kurtz for a 23-yard strike with 37 seconds left. The Cougars could not recover the ensuing onside kick and UCLA ran the clock out.