TUCSON, Ariz. -- Arizona played without its starting quarterback and its most productive running back, a combination that would have likely led to disaster last season.
This year's Wildcats have a different kind of swagger to them.
Back-up quarterback, multiple running backs having to carry the load, young players in key positions -- doesn't matter to them.
"These guys are learning on the run, they're growing up," Arizona coach Kevin Sumlin said. "To play in the last two games the way they've played down the stretch, for a young football team (it's big)"
Gunnell had seen spot action earlier this season, but was making his first collegiate start. The freshman played like he had been the starter all along, keeping his poise while completing 29 of 44 passes.
"I have full confidence in Grant," Arizona linebacker Tony Fields said. "He deals with us in practice every day and somehow, some finds a way to make plays like he did tonight."
UCLA (1-4, 1-1) pulled off an epic comeback last week, rallying from 35 points down to beat Washington State. The Bruins needed another, not-so-monumental comeback after Gary Brightwell scored on a 10-yard run to put Arizona up 20-17.
His replacement, sophomore Austin Burton, had a chance when UCLA forced a punt and got the ball at its 9-yard line with 2:52 left.
Burton worked the Bruins down the field quickly to Arizona's 21-yard line, but Molson pushed his field goal attempt wide right with 34 seconds left.
"He's made a lot of big kicks for us," UCLA coach Chip Kelly said. "It's unfortunate it comes down to a kick at the end of the game. There's a lot of other plays you could make where it doesn't come down to a kick."
UCLA saved its season and potentially Kelly's job last week with its 67-63 comeback win over then-No. 19 Washington State.
Thompson-Robinson had a school-record 564 yards of offense while accounting for seven touchdowns and looked like he was going to slice right through Arizona's defense as well.
UCLA went 85 yards -- 40 on Thompson-Robinson runs -- in 12 plays on its opening drive and scored on Matt Lynch's 2-yard touchdown catch.
The Bruins sputtered after that, managing 100 yards the rest of the half.
Arizona was a little better at moving the ball -- well, until it got to the red zone. The Wildcats crossed UCLA's 20-yard line three times in the first half and stalled each time, settling for two Lucas Havrisik field goals and another he missed.
Arizona didn't take long to get going in the second half, scoring on its first play when Darrius Smith took advantage of a breakdown in coverage by UCLA and streaked along the sideline alone for a 75-yard touchdown.
"You rush three, drop eight into zone and they throw the ball over your head," Kelly said. "That's a bit of a backbreaker."
UCLA answered after Thompson-Robinson went down, scoring on a 3-yard run by Joshua Kelly after he broke off a 36-yard run to put UCLA up 17-13. Arizona again had its own answer, scoring on Brightwell's run and surviving the potential game-tying kick.
UCLA lost its starting quarterback and another chance at a comeback victory when Molson missed his kick.
Arizona pulled out a gritty win without two of its best players and may be hitting its stride after a disappointing season-opening loss to Hawaii.
Arizona appeared to have a game-clinching touchdown midway through the fourth quarter when Brian Casteel caught a screen pass, broke a couple of tackles and raced into the end zone.
One problem: His knee was down when he caught Gunnell's pass.
So instead of a 42-yard score, Arizona took a two-yard loss and ended up punting the ball away after failing on a third-down try.
UCLA hosts Oregon State next Saturday.
Arizona plays at Colorado next Saturday.
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