Tuitama directed the Wildcats 80 yards in 11 plays, capping the decisive drive with a pass to Thomas in the back of the end zone. Arizona scored 22 points in the fourth quarter to ruin an outstanding performance by Washington quarterback Jake Locker.
The Huskies led 41-26 with 12:32 left.
Tuitama completed 38 of 51 passes and threw for five touchdowns. He bested the previous record of 492 yards by Jason Johnson against California in 2002. Arizona (3-6, 2-4 Pac-10) snapped a three-game losing streak and, for the moment, took some heat off coach Mike Stoops. Thomas had 10 catches for 165 yards and three touchdowns.
Washington's losing streak was extended to six games in shocking fashion, as its defense failed to come through for the second straight week.
Against Oregon, the Huskies had allowed a school-record 465 rushing yards. This week, it was their pass defense that struggled and canceled out Locker's stellar day.
Locker had career highs in rushing (157) and passing (336). But the Huskies could not overcome four turnovers, the last of which led to Arizona's tying points midway through the fourth quarter.
Washington built the 41-26 lead when Luke Kravitz plunged in from 1 yard. But Ryan Perkins missed the extra point attempt.
Tuitama quickly answered, taking less than 90 seconds to find Terrell Turner for a 33-yard touchdown. On Washington's next series, Locker and running back Louis Rankin fumbled the handoff exchange and Arizona linebacker Spencer Larsen recovered at the Washington 30, his second fumble recovery.
Four plays later, Tuitama hit Thomas on a fade route for a 2-yard touchdown, then found Thomas for the 2-point conversion to tie the score at 41.
Arizona's defense held, and Tuitama directed the Wildcats 80 yards for the winning score. Tuitama was perfect on the winning drive, completing all eight passes capped by finding Thomas, who corralled the throw behind leaping Washington cornerback Roy Lewis.
Washington had one final chance, driving into Arizona territory with under a minute remaining. Locker just missed hitting either Cody Ellis or Anthony Russo in the end zone on a deep throw, then Antoine Cason ended the hopes with his fourth interception of the season at the Arizona 37.
Washington's offense was nearly unstoppable in the first half, racking up 415 yards. But the Huskies' lead was only 28-23 at the break after they fumbled on their first two possessions, once by Locker and once by Rankin, both on drives inside the Arizona 40.
After Rankin's fumble, Tuitama needed just two plays to take advantage. Thomas dropped a wide open deep throw on the first play, but cradled Tuitama's second shot downfield for a 66-yard TD, the Wildcats' longest play this year.
Locker added a 14-yard touchdown run, picking up a dropped snap, then making two Wildcats miss before spinning into the end zone. In the second quarter, Locker found Marcel Reece for a 98-yard touchdown pass, the longest play in Washington history. The previous long was Sterling Hill's 94-yard TD run in 1898.
Locker became the second quarterback in Washington history to run for at least 100 yards and pass for at least 300. Marques Tuiasosopo rushed for 207 and passed for 302 against Stanford in 1999.
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