The difference between what is and what could be for Penn State running back Mike Gasparato is gaping.

What is: Gasparato is a virtually anonymous backup who is lucky if he ever gets on the field during the game.

What could be: Gasparato could be in one of the most heralded positions in college football.

He could be in the spotlight playing the position of former Nittany Lions Blair Thomas and D.J. Dozier, whom he grew up around while his father Nick was an assistant coach for the Lions.

And for all the time he is spending in his reality, he has to be constantly preparing himself for what could be, because all that separates the two is one man.

There are times when tailback Larry Johnson may seem like more than just that.

He has become one of college football's most explosive playmakers. He's tops in the Big Ten in all-purpose yards, and ranks second in the nation in the category.

But he is just a man, and though his strength makes him durable, he doesn't have any magic power that makes him immune to injury.

And when he gets bumped up, Gasparato gets to leave what is, and get a taste of what could be. When he does, he has to handle everything that comes with that and make sure his team doesn't suffer.

"I've been telling everyone my goal this year is when Larry goes out of the game, to go in there and have the offense not skip a beat," he said. "You have to go in there just believing that you can play. You've got to be able to take the pressure off your shoulders because you don't have time to be nervous ... You have to go in there and perform."

Last Saturday against Wisconsin was the first time Gasparato was placed in such a situation. When Johnson strained his hamstring in the third quarter, Gasparato was suddenly the Nittany Lions' tailback. Before that game, the redshirt sophomore had only four carries as a college player, three of them coming late in the Lions' blowout victory against Louisiana Tech.

"I was just telling myself, it's time to go, you've got to show up now," Gasparato said. "I figured one of these days you get your chance. That's usually the way it goes. You have to make the best of it, and you can't mess up because you might not get another chance."

He rushed six times for only 13 yards, but did make a 25-yard reception in a first-and-25 situation after a personal foul on the Lions.

His performance wasn't Johnson-like, but Penn State football coach Joe Paterno said he was happy with the way his backup running back filled in. His comments at his press conference Tuesday showed that he is much more confident in his running back situation than he had been earlier in the season and during the spring.

"I kind of agreed with him at first, because I didn't think I was playing that well, and I thought I could, but I just needed more practice," Gasparato said. "I didn't think I was doing everything well enough to be a Penn State tailback for a while there, but I pulled it together."

Paterno said that he expected Johnson to be back in the lineup tomorrow, but Gasparato is making sure he's ready for what could be.

"You have to prepare every week like you're going to play a lot," Gasparato said. "In my mind, I have to be ready to play on any play. You can't get lackadaisical on the sidelines and something happens, and for whatever reason you have to make a play in the game ... I have to be ready to go at all times."