PASADENA, Calif. -- Seven lead changes and a touchdown by each team in the last minute of the game resulted in euphoria for one and misery for the other.

Sophomore quarterback Luke Falk tossed a 21-yard floater to wide receiver Gabe Marks for a touchdown with three seconds remaining on Saturday night that catapulted Washington State to a stunning 31-27 upset victory over No. 19 UCLA.

"Obviously a very disappointing loss for us," UCLA coach Jim Mora said. "It's a very disappointed locker room. That is something that we have to get over quickly."

The game, witnessed by 76,255 at the Rose Bowl, made Washington State (7-3, 5-2 Pac-12 North) bowl eligible. UCLA dropped to 7-3 overall and 4-3 in the PAC-12 South.

"It was a good one. They all are," Washington State coach Mike Leach said. "Maybe next week if we play good at Colorado that'll be a good one, too."

Falk drove Washington State 75 yards in seven plays, taking barely a minute to do so, for the winning score. The key play on the drive was a 30-yard completion down the middle to wide receiver Dom Williams.

"They made plays," Mora said. "We were playing (man-to-man). We were trying to take care of the corners and double up some things."

The Cougars' comeback thwarted true freshman quarterback Josh Rosen's attempt to rally the Bruins. Rosen completed 33 of 57 passes for 340 yards and rushed for a season-high 70 yards.

Barely a minute before Falk's winning pass, Rosen took UCLA 80 yards in 10 plays, capping the drive with a 37-yard touchdown scramble through a defense that had dropped deep to take away the pass. Rosen's two-point conversion pass to Thomas Duarte gave the Bruins a 27-24 lead.

But with 1:09 left, Falk had enough time to reply.

"A lot it is that Luke is so stable," Leach said. "He has a very calm and stabilizing influence on our offense."

Earlier, it looked like Falk might not be around to become the hero. He landed heavily on his left shoulder in the first half after being mashed hard to the turf on a pass. He was taken to the locker room for observation and treatment.

"He's a tough person, a tough player," Leach said. "He played tough down the stretch. We're really proud of him."

Falk's backup, Peyton Bender, was up to the task. After UCLA took a 13-7 lead on a 14-yard run by Nate Starks, Bender hooked up with Williams on a 7-yard touchdown pass after Washington State recovered a fumbled punt by UCLA's Ishmael Adams.

Falk returned in the second half and continued the passing that made him the national leader in yards per game. Falk, who came in averaging 415 passing yards, completed 38 of 53 attempts for 331 yards and two touchdowns.

The UCLA defense sacked him six times and knocked him to the ground several other times.

UCLA lamented two first-half drives that should have resulted in touchdowns but were reduced to two of the four field goals by record-setting senior Ka'imi Fairbairn.

"The two drives that come to mind are when we had the ball not just in the red zone but deep in the red zone, around the 2-yard line," Mora said. "And we couldn't capitalize with sevens. We had to settle for threes."

NOTES: UCLA K Ka'imi Fairbairn became the leading scorer in Pac-12 history, breaking the mark held by former UCLA kicker John Lee (390 points from 1982 to 1985). Fairbairn has 402 points in his career. ... Washington State sophomore RB Gerard Wicks was a teammate at Long Beach Poly with Bruins DB Randall Goforth and LB Jayon Brown. ...

Gabe Marks caught 12 passes for Washington State. Jordan Payton tied a UCLA school record by catching 14 passes. ... UCLA senior C Jake Brendel started his 49th game, the most in school history. It broke a tie that Brendel had with former Bruins linebacker Spencer Havener (2002-2005). ... Bruins junior RB Paul Perkins rushed for 121 yards, the 11th 100-yard game of his career. Perkins' season rushing total is 1,082 yards, the second consecutive year that he has reached 1,000 yards.