Hours before the Eagles played the Pittsburgh Steelers in a preseason game in August 2008, Howie Roseman visited the University of Pittsburgh's football practice to scout a team with a collection of prospects - including a precocious sophomore named LeSean McCoy.

Pitt's offense was backed up on its 1-yard line during a scrimmage, and the play called for a handoff to McCoy. He reversed field and ran 99 yards for a touchdown, eluding tacklers and accelerating past the defensive backfield. Roseman turned to a friend on Pitt's coaching staff and asked if he had ever seen a running back run like that.

"Tony Dorsett," the coach responded.

"It was hard not to leave with a lasting impression," Roseman said last week.

Since then, McCoy has become one of the marquee players on the Eagles and the perfect running back for this incarnation of Andy Reid's offensive system.

On Sunday, McCoy will show what he's become when the Eagles play the Steelers at Heinz Field, the site of McCoy's college home games and five miles from where Roseman watched him that August summer day four years ago. He'll be a central part of the offense and a critical component to beating a Steelers defense with a reputation for stopping the run.

It's not the number

There's a common Monday debate in Philadelphia about how many carries McCoy should have received the day before. The idea that he doesn't carry the ball enough can sometimes be inaccurate - after all, he had the seventh most carries in the NFL last season, and has the fifth most in the league this year. But the notion that the Eagles sometimes abandon the run is fair.

The key with McCoy is for the Eagles to give him enough runs to create big plays. McCoy has averaged 4.8 yards per carry in his career, although his path is seldom 4- or 5-yard rushes. McCoy can run the ball for 1 or 2 yards for four consecutive carries before busting a 20-yard run.

"What you have to train people to understand is that at the end of the day, that's what you're going to average," running backs coach Ted Williams said. "Because every run ain't going to be like that. There's going to be a lot of runs that ain't 4.5. But it's better to be 0, 1, or 2 than it is to be minus-5, minus-3, minus-1. I tell him all the time, no negative runs."

The best example came in last week's win against the Giants. McCoy struggled in the first half, rushing for only 2 yards on six carries and was stuck at eight carries for 6 yards during the first drive of the second half. Still, the Eagles continued handing him the ball - and McCoy's next two rushes yielded 34 yards and 22 yards. Within a minute, his average increased from 0.75 yards per carry to 6.2. By the end of the game, McCoy carried 23 times for 123 yards, with 107 of the yards coming on six carries.

"I just run and look at the stats at the end of the year," McCoy said. "But a lot of the times, it's guys downfield getting blocks. Those blocks kind of spring the backs, and you'll probably see that every time you see a back break out. Guys downfield picking up the block."

McCoy said the long runs start with the offensive line and requires the right call at the right time. He also praised first-year fullback Stanley Havili, who was a major contributor last week. The key is for the runner to create a one-on-one situation against an opposing defender.

"Any of the backs - not just me - but any of the backs, you give a one-on-one situation," McCoy said, "nine times out of 10, we're going to win them."

McCoy leads the NFL in rushes of more than 10 yards this season with 13, and those within the Eagles' complex describe his ability for those plays as a natural combination of athleticism and vision. Williams conducts a drill in which the running backs must run 50-yard dead sprints, and Williams measures the amount of strides required in the first 10 yards. The longtime running backs coach praised McCoy's stride, which is vital in beating a defender around the corner and accelerating.

It's also why McCoy is an ideal fit in the Eagles offense, which relies on big plays, with skill position players who can turn a 5-yard gain into a 50-yard gain. The Steelers are usually adept at preventing those kind of plays, making Sunday's matchup so intriguing. The Steelers allowed the fewest runs of at least 20 yards in three of the last five seasons, and they allowed the second-fewest in one of those years.

Yet Oakland's Darren McFadden scored on a 64-yard run against the Steelers two weeks ago, the longest touchdown run the Steelers have allowed since Mike Tomlin became head coach in 2007. McFadden gashed the Steelers for 113 yards on 18 carries, leaving Pittsburgh with a sour taste entering last weekend's bye.

The Steelers have not allowed consecutive 100-yard rushers since 2002, a revealing mark that McCoy will attempt to break. Pittsburgh's defense is allowing 4.3 yards per carry this season, although they will be bolstered by the return of safety Troy Polamalu and outside linebacker James Harrison.

The two styles will clash Sunday, but don't expect McCoy to try to run between the guards or become a bruising back. That's not the style that propelled McCoy from high school to the 99-yard run during a Pitt preseason scrimmage to last week's two long rushes against the Giants.

"You can't fit a round peg into a square hole," Williams said. "You can't make him be Eddie George. You can't make him be Arian Foster. He's who he is - and you got to take who he is, and what his gifts and talents are, and enhance them to the betterment of the team."

'Something I can't teach'

When McCoy was at Pittsburgh, he spent Saturdays dominating Big East defenses and some Sundays at Santonio Holmes' house watching the Steelers. He rushed for 1,488 yards and 21 touchdowns during his redshirt sophomore season, which was the second most of all college runners.

When Williams assesses college running backs, he tries to identify a certain type of player: "somebody who has something I can't teach." With McCoy, it was the ability to make defenders miss and the quickness through a hole.

So after the Eagles selected Jeremy Maclin in the first round of the 2009 draft, they attempted to trade into the late first round or early second round and select McCoy. They were able to wait until the No. 53 overall pick, and McCoy has improved every year since arriving in Philadelphia.

Sunday marks his first regular-season game in his college stadium. He has secured tickets for friends and family and expressed excitement about playing where he created so many memories. But the impression on the Eagles was actually made five miles away, where Roseman saw him reverse field and run for that 99-yard touchdown.

"You don't forget moments like that in a college practice," Roseman said.

Even McCoy didn't forget it. When told of the play in the Eagles locker room Friday, he smiled and remembered cutting and sprinting past the defense. Then, when asked if he thought that play influenced the Eagles' drafting of him, he smiled again.

"I think it was the 21 touchdowns," he said.