USC has seen this ending before against Washington

It qualifies as college football’s closest, if not the most popular, social network.

USC Coach Lane Kiffin and Washington Coach Steve Sarkisian matured together as assistants under Pete Carroll and are part of a coaching tree that extends into both staffs. Those relationships produced text messages and other light-hearted communiques throughout the week and lots of pregame handshakes and hugs before kickoff Saturday night at the Coliseum.

But when the game was over, Sarkisian posted a status update straight from the in-your-face book.

Just as they did last season in Seattle, the Huskies put together a drive in the final minutes and beat the Trojans with a field goal by Erik Folk as time expired.

Folk’s 32-yard kick, his fourth field goal of the game, gave the Huskies a 32-31 victory that knocked USC from the ranks of the unbeaten and gave Kiffin his first defeat.

The Trojans are 4-1 overall and 1-1 in Pacific 10 Conference play heading into next week’s grudge-match game at Stanford.

But it might take the Trojans a while to get over another loss to Sarkisian and quarterback Jake Locker, who spoiled a 223-yard rushing effort by USC tailback Allen Bradford.

As he was last season in leading the Huskies to a 16-13 upset, Locker was clutch when his team needed him most.

The 6-foot-3, 230-pound senior, who began the season projected as the possible No. 1 pick in the NFL draft, bounced back from an embarrassing performance against Nebraska two weeks ago.

He completed 24 of 40 passes for 310 yards and a touchdown without an interception, and rushed for 111 yards in 12 carries.

“That was the worry all week, that he’d play like that,” Kiffin said.

USC led 21-20 at halftime and 28-23 late in the third quarter before Locker engineered a scoring drive that backup Keith Price finished with short touchdown pass after Locker was temporarily hurt on a sneak.

USC went ahead, 31-29, on Joe Houston’s 27-yard field goal with 10 minutes left, but Houston’s 40-yard attempt with 2:34 remaining hit the right upright, giving Locker one more chance.

Starting at his own 23, Locker’s first pass was incomplete. But his 18-yard strike to D’Andre Goodwin on fourth-and-11 kept the drive alive. Running back Chris Polk followed with a 26-yard gain to USC’s 33, putting Washington in position to call on Polk.

Locker’s eight-yard run and Polk’s one-yard run advanced the ball to the 15. USC called timeout twice to try to freeze Folk, but he coolly split the uprights for the victory.

On a night when the Trojans broke out the wildcat formation for the first time, junior Marc Tyler enjoyed a productive game, gaining many of his 60 yards on direct snaps.

But it was Bradford, who sat out Thursday’s practice because of back soreness, who kept the Trojans in the game.

The senior from San Bernardino scored from 37 yards the first time he touched the ball and his 16-yard touchdown in the third quarter gave USC a 28-23 lead.

But the Trojans missed several opportunities.

USC quarterback Matt Barkley went into the game with a nation-leading 12 touchdown passes and was ranked 14th in passing efficiency. Barkley, though, had had two passes intercepted in each of the last two games.

Barkley did not commit a turnover against the Huskies — he completed 14 of 20 for 186 yards — but he chided himself for missing on a couple of attempts that might have resulted in touchdowns.

“Sometimes I was too focused on not throwing interceptions on some of those clutch drives,” he said.

Locker had no such problem.

Folk, a junior from Sherman Oaks Notre Dame High, also maintained his focus, kicking field goals of 23, 41 and 35 yards before his game-winner.

Washington receiver Jermaine Kearse caught six passes for 92 yards and Devin Aguilar had five receptions for 83 yards, including a 44-yard touchdown.

gary.klein@latimes.com

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