The cat is out of the bag and that could prove to be a benefit to Steelers when they host San Diego in the AFC playoffs Sunday.

Despite his diminutive size, Darren Sproles, a star player at Kansas State, hasn't quite found his niche in the NFL, although he has been somewhat successful as a return man for the Chargers.

His incredible game in last Saturday's 23-17 overtime victory over the Indianapolis Colts — 23 carries for 105 yards, five catches for 45 yards, 106 yards on four kickoff returns and 72 yards on three punt returns for a whopping 328 total yards — came at just the right time.

If LaDainian Tomlinson hadn't been slowed by an injured groin, Sproles, all 5 feet, 6 inches of him, might not have had a chance to shine. If Tomlinson had played more than 1Z\x quarters, no one might have expected Sproles to run wild.

The surprise could have been against the Steelers, who might not have known what to expect if Tomlinson would have left the game much later.

The Steelers could have been embarrassed while hosting a game against the Chargers, who finished 8-8 during the regular season but have reeled off five consecutive wins.

The Steelers' special teams have improved since last season, but they now have one week to try to figure out how to slow Sproles as opposed to learning on the fly if it would have happened in the game.

Is Sproles still dangerous? Yes, he is. Sproles came out of KSU, where he led the Wildcats to the Big 12 championship game, but couldn't quite make a breakthrough in the NFL.

He has subbed behind Tomlinson, the game's best running back and top fantasy player, the past four seasons. The Chargers thought enough of him that they let Michael Turner leave via free agency.

Turner had a monster season with the Atlanta Falcons, but Sproles has taken the reins, doing everything head coach Norv Turner has asked of him.

Entering the postseason, Sproles has rushed for 330 yards on 61 carries (5.4 yards per carry) and one touchdown and 342 yards receiving on 29 catches (11.8) and five scores.

He is averaging 26 yards per kickoff return (53 for 1,376 yards, 1 TD) and 11.3 yards per punt (22 for 249 yards).

If Tomlinson, who appeared in obvious discomfort on the sidelines in the second half doesn't play Sunday, the bulk of the load will be on Sproles' shoulders.

He's shown he can handle the load in one game. Maybe he can do so as the Chargers try to run the table and reach the Super Bowl.

Despite their talents, the knock on players like Sproles is their size. At 181 pounds, Sproles isn't looked upon as an every-down back, someone who could carry 25 times a game.

Players such as Barry Sanders have been small, but have a physical side as well. Whether Sproles can put himself in Sanders' class remains to be seen.

The Steelers must contain Sproles, but they can't let quarterback Philip Rivers go unnoticed. But Sproles must be accounted for on every play.

That's something no one might have thought about last week.

Sam Tallarico is a staff writer for the Butler Eagle.