The win capped another strong year for the No. 20 Broncos (11-2), who had to overcome a 205-yard rushing game by Bishop Sankey against their normally stingy defense. Sankey also had 74 yards receiving, giving him 279 of Washington's 447 yards from scrimmage.
But it was Frisina who came up with the biggest game of his career in his final game. He kicked three field goals, including the first game-winner he could ever recall booting.
"It's every kicker's dream to win a big game with a field goal," Frisina said. "For this one to come on the last game of my career, you couldn't ask for anything more.'
Washington (7-6) had taken the lead for the first time on a 38-yard field goal by Travis Coons with 4:09 left when No. 20 Boise State got a big kickoff return by freshman Shane Williams-Rhodes to the Washington 42. Joe Southwick guided the team to the 12 before Frisina hit the winning kick.
"I was just focused on what I had to do," Frisina said. "I'm there as the insurance guy, I guess you'd say."
Boise State sealed the win when Jeremy Ioane intercepted Keith Price's pass as the Huskies neared midfield.
"To their credit, they found a way to win the game in the end," said Washington coach Steve Sarkisian. "Our inability to finish is pretty blaring."
Sankey, who was third on the depth list when fall practice began, rushed 30 times and caught six passes in the biggest game of his career. He scored one touchdown and was the MVP of the game, despite being on the losing side.
"There's a lot of mixed emotions going on," Sankey said. "The MVP doesn't mean so much when you come out a loser."
Frisina was only 12 for 17 on field goals coming into the game, but kicked three of them, including a 34-yarder to open the scoring that was his first field goal of more than 30 yards for the year.
Southwick, meanwhile, had another efficient game,completing 26 of 38 passes for 264 yards and two touchdowns for a Boise State team that struggled offensively through much of the season before improving over its last three games.
Southwick also ran for 39 yards and had a punt that pinned Washington by its goal line in the fourth quarter.
Leave it to the kicker
O Boise State's Michael Frisina kicks the game-winner to lift the Broncos.
• Washington's Bishop Sankey won the MVP award for his 279 yards of offense.