Served bowl leftovers, will Trojans get the stuffing beaten out of them?

USC’s leading rusher is in limbo because of a school compliance investigation.

Three other key players are academically ineligible.

And the Trojans, who thought playing in the Rose Bowl on New Year’s Day had become old hat, have a history of struggling in some December bowl games.

Not exactly the most desirable set of circumstances, but USC players said they were motivated for today’s Emerald Bowl against Boston College.

“To the outside person that’s not on the team, who has a normal job everyday, they talk like it’s distracting,” senior safety Taylor Mays said. “When you do it like we do every day, you develop mental toughness that gets you through it.

“That’s what our guys will be able to do.”

Coach Pete Carroll certainly hopes so.

The Trojans were recently accustomed, for better or worse, to playing annually in Pasadena in January in one of college football’s most venerable stadiums.

But after losing three of their last five games and finishing 8-4, they’re about 380 miles north, playing in AT&T Park, a baseball stadium that requires both teams to share a sideline.

Nevertheless, Mays and others said motivation won’t be an issue against an 8-4 Boston College team that was picked to finish last in its division in the Atlantic Coast Conference.

For USC seniors and other draft-eligible players pondering a jump to the NFL, the game against the Eagles offers a final chance to flash their talent for pro scouts.

For first-year starters such as quarterback Matt Barkley and linebackers Chris Galippo and Malcolm Smith, it is an opportunity to cap a roller-coaster season on a high note.

And for others such as freshman offensive tackle Matt Kalil, who will make his first start, there is a chance to impress heading into the off-season and spring practice.

“Everyone has something to play for,” Galippo said. “We want to finish with a bang.”

The Trojans’ offense, which has struggled to perform consistently, potentially lost some of its firepower when USC began investigating starting tailback Joe McKnight’s use of a sport utility vehicle that is owned by a Santa Monica businessman.

McKnight practiced with the Trojans in Los Angeles on Monday but did not join the team in the Bay Area until late Wednesday night.

He practiced Thursday, but as of Friday his availability for the game was still undetermined.

Earlier this week, senior tight end Anthony McCoy, freshman offensive tackle Tyron Smith and senior defensive lineman Averell Spicer were ruled out of the bowl game because of academic issues.

McCoy and Smith were starters, Spicer a regular in the defensive-line rotation.

“More than anything, it just feels like the guys are injured in that regard -- that they’re not available to you,” Carroll said.

After their season-ending loss to Arizona on Dec. 5 at the Coliseum, several players said the Trojans had lacked the emotion that had helped them defeat rival UCLA, 28-7, a week earlier.

So it remains to be seen whether the Trojans will be inspired to play in front of a crowd of less than 50,000 the day after Christmas.

USC has a 5-7 record in bowls other than the Rose Bowl or other Bowl Championship Series games.

And third-tier games have been particularly nettlesome.

Michigan State edged the Trojans in the 1990 John Hancock Bowl, Fresno State beat them in the 1992 Freedom Bowl, Texas Christian defeated USC in the 1998 Sun Bowl, and Carroll’s first season at USC ended with a 10-6 loss to Utah in the 2001 Las Vegas Bowl.

That game was regarded as a reward for a team that finished the season with four consecutive victories.

The USC team that takes the field today stumbled through the second half of a season that began with national-title aspirations.

Despite McKnight’s situation and the loss of the ineligible players, Carroll said the Trojans were looking ahead, not behind.

“Guys are jumping at this chance and hopefully they can do something with it,” he said.

gary.klein@latimes.com

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