Chargers running back Darren Sproles is now the darling of the NFL. Stepping in for LaDainian Tomlinson, he ran for 105 yards and added another 223 yards on receptions and kick and punt returns.

He becomes the focal point for the league's best defense and one of its best special teams coverage units.

Sproles has excellent vision and his diminutive size is an advantage running between the tackles - it seems tacklers just lose him in the crowd, and he's able to squirt forward for extra yards.

The truth is, though, Sproles is a by-product of a Chargers offense that is consistenly succeeding on the ground and through the air. Their offensive numbers weren't tremendous - 357 total yards is good, not excellent - but 26 first downs and 4.9 yards per carry are numbers which which teams can win in January. They lost eight regular season games largely in part to their defense not being able to get one stop when they needed it, but against league MVP Peyton Manning, they were able to keep Manning from beating them late in the game.

Sproles was the key on offense all game.

One play of many stands out. It's 7-rip Indianapolis, Chargers have the ball on their own 24 yard line. It's third and eight, San Diego brings out a 4-WR set, including splitting out Antonio Gates in the slot to Rivers' right.

Rivers hands off to Sproles on a jet right 24 sprint, all-world guard Kris Dielman pulls from left to right and blows up DE Raheem Brock. Sproles cuts off that block, makes LB Freddie Keiaho miss and eventually is twisted down for a 14-yard gain. It was a fantastic play, one that saw four receivers get blocks down the field, a guard execute perfectly and the running back make his one guy miss.

No running back, no team no running scheme calls a run on 3rd-and-8 without possessing a tremendous amount of confidence. No team unable to win on the road in the post-season converts third-and-long with their back-up running back out of a four receiver set on the ground.

Very impressive for Sproles, very impressive of the Chargers.

Question is for Pittsburgh, does that level of execution show more of the Colts' failure to recognize the play (they had their nickel on the field), or is San Diego really that hot? With all due respect to the Chargers, but the Colts aren't comparable to Pittsburgh defensively.

Dielman is as good a guard as they come in the NFL, but is Steelers LB James Farrior missing that tackle? I'm sure he's watching that play and seeing how Sproles is a vastly underrated inside-the-tackles runner, and his ability to change directions should be taken with a high level of concern.

He picked up 14 yards on that play, and 22 yards on the game-winner in overtime, which, combined, accounted for 36 of his 105 yards on the day.

It's not so much Sproles as it is a well-managed and well-executed offense that will challenge the Steelers Sunday. TE Antonio Gates had eight catches for 87 yards, but most of them set up 2nd or 3rd and short, and his 30 yard catch-and-run set up LaDanian Tomlin's touchdown. He beat CB Kelvin Hayden off the snap with an inside move, and nearly outran the rest of the Colts defense inside the five.

These two plays are enough to show the Steelers they are in for a fight. With an offense that can run for success from a 4-WR set and a tight end that can beat a cornerback to the inside, combined with a quarterback who had nearly a 3-to-1 TD-to-INT ratio this season shows the Chargers can attack defenses in a variety of different ways.

The Steelers are known for nullifying such advantages, though, and if they are able to maintain gap discipline on the line and their linebackers fly to the ball and gang-tackle as usual, they will be able to contain San Diego's offense.