-- For complete coverage of Saturday's USC-Syracuse game, click on our Game Week link or follow us on Twitter. --

For several years, the Olympic Cauldron at the Los Angeles Coliseum has been lit before the start of the fourth quarter of USC football games.

This season, it could also be used as a distress signal for the Trojans' offense.

In the first two games of 2011, USC had fourth-quarter leads and many chances to put the game out of reach, or at least make sure their opponents had fewer chances to make it a ballgame.

But the Trojans offensive unit has struggled late in games. USC's offense has averaged 6.2 yards per play in the first three quarters of action. But in the 4th quarter, they've fallen back to 4.2 yards per play.

When 'SC has needed a long drive to cinch the game, they have not been able to get it done. The offense has averaged just 4.7 plays per drive in the fourth quarter, and only one out of seven drives has gone more than five plays.

Without the offense's ability to strangle the life out of opposing teams, the Trojans have been forced to rely on strong defense and special teams, including a last-minute Torin Harris interception against Minnesota and Matt Kalil's field goal block to cinch the victory over Utah.

For some reason, QB Matt Barkley's numbers have taken a step back during the fourth quarters of games. Take a look at the difference between the two such game situations over his 26-game USC career:

And this is not exactly a small sample size: Barkley has had 678 dropbacks in quarters 1-3 during his career, and 162 dropbacks in the fourth.

However, much of the blame for opposing teams sticking around has to do with the play calling of head coach Lane Kiffin. When your team has the lead in the fourth quarter, the goals should be to run down the clock and add some insurance points, often in that order. Thus, most coaches deploy a run-first strategy with designs on accomplishing both of those goals.

Clearly Kiffin is not most coaches. In the fourth quarter this season, he has called 16 pass plays (which have averaged 4.0 yards per play) and just 14 run plays (5.4 yards per play). And the clock has stopped on seven incompletions among those 16 pass calls.

Clock stoppages hurt the Trojans against Utah. On Saturday, USC started drives with 12:27, 8:59 and 6:04 left in the game, but couldn't bleed the rest of the time. All three of those drives went for four plays or fewer, took less than 2:30 off the clock, and each included an incomplete pass that froze the clock.

On the fourth drive, which started with 2:08 left, Kiffin called Marc Tyler's number three times. The senior running back got nine yards, but couldn't finish off the game with a first down.

But if USC goes up on Syracuse this coming week, Kiffin should keep going to Tyler.

In 2010, Tyler averaged 4.8 yards per carry in the first three quarters of the game, which is pretty good. Then he hit his stride in the 4th quarter, averaging 8.1 yards per rush on 27 attempts. Even if you take out the possible outlier of his 44-yard touchdown run in the fourth quarter at Hawaii, Tyler still averaged an impressive 6.8 yards per carry.

The theory is that defenses get worn down as games go on, allowing a large running back like the 230-pound Tyler to power through for more yards in the second half. And it has worked thus far, with Tyler gaining about two more yards per carry on fourth quarter runs last season, and averaging 4.8 yards per rush on eight fourth quarter attempts against Utah.

USC's offense was bailed out by its defense in the fourth quarter Saturday's game, including two third-down sacks on Saturday of Utah QB Jordan Wynn.

Often times, however, the winner of a close game (read: seven points or less) has more to do with luck than skill. Over a large sample of games, the ability to blow out inferior opponents is a greater indicator of future success than close victories against good teams.

That's why it is important to suck the life out of the opposing team when your team gets a late lead and the football.

By calling more running plays, letting Tyler and his offensive line create first downs, Kiffin can extinguish the hopes of the opposition.

Just like blowing out a candle.

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Reach James by email or follow him on Twitter, @JamesSantelli.