SAN FRANCISCO — Matt Barkley threw touchdown passes to Stanley Havili on Southern California's first two possessions and added a touchdown run in the fourth quarter to help the Trojans beat Boston College 24-13 in the Emerald Bowl tonight.

The victory was far from impressive but it did put a positive ending on a disappointing season for USC (9-4). The Trojans lost three of their final five regular-season games to fall out of the national rankings for the first time since Pete Carroll's first season as coach in 2001.

That left USC in an unfamiliar bowl setting after making it to the Bowl Championship Series the past seven years, including four straight Rose Bowl bids. But the Trojans made the most of it, handing Boston College (8-5) its second straight bowl loss after an eight-year bowl winning streak.

Damian Williams caught 12 passes for 189 yards in what could be his final game for the Trojans, grabbing long passes to set up Havili's second score and Barkley's 1-yard sneak that gave USC a 24-13 lead with 11:53 remaining. Williams is expected to skip his senior season to enter the NFL draft.

The Eagles stayed close with the Trojans for most of the game before Dave Shinskie threw an interception to Shareece Wright early in the fourth quarter. On the next play, Barkley connected on a 48-yard pass to Williams, who made a leaping grab between three defenders. Barkley scored on the next play.

The Trojans won despite playing without leading rusher Joe McKnight, who was not cleared to play as the school investigates whether he violated rules by using an SUV that doesn't belong to him. McKnight is USC's first 1,000-yard rusher since 2005, with 1,014 yards on 6.2 yards per carry and eight touchdowns.

USC struggled on the ground without McKnight but was able to move the ball consistently through the air as Barkley often found open receivers on slant patterns. Barkley completed 27 of 37 passes for 350 yards in the second 300-yard game of his freshman season. He also threw two interceptions that allowed Boston College to stay close until the fourth quarter.

The Trojans got a fast start by scoring touchdowns on their two possessions with passes from Barkley to Havili to go up 14-0. But USC didn't score again in the half, with Barkley throwing an interception deep in BC territory to end one potential scoring drive.

The Eagles got right back into the game with a 7-yard run by Montel Harris. Steve Aponavicius hit the upright on the extra point attempt, ending a streak of 81 straight makes since late in the 2007 season.

BC got help from a big mistake by USC to get another score late in the half. Michael Morgan was called for pass interference on a third-and-21 toss to Chris Pantale that went only 2 yards. But the infraction gave the Eagles an automatic first down and Shinskie connected with Rich Gunnell on a 61-yard TD pass on the next play to make it 14-13.

Gunnell finished with six catches for 130 yards, breaking Pete Mitchell's school record for yards receiving with 2,659 in his career.

The Eagles missed a golden opportunity to score after intercepting Barkley on the first play of the second half to give them the ball at the 9. Harris fumbled a handoff two plays later, costing BC a chance to take its first lead of the game.

Harris finished with 102 yards on 23 carries for his fifth straight 100-yard game, but BC struggled to move the ball in the second half. The Eagles had just 19 yards in the third quarter and never mounted a sustained drive in the second half until the game had been decided.

Shinskie was 14 for 33 for 218 yards and the interception.