Kain Colter is a quarterback, a running back, and a wide receiver, and that's fitting because opposing defenses swear they are chasing three guys whenever he's on the field.

Colter is not a big man at 6 feet and 190 pounds, but the Northwestern junior has become one of the ultimate weapons in the Big Ten Conference, able to make a big play at any time at any of the three positions.

When the 24th-ranked Wildcats meet Penn State on Saturday at Beaver Stadium, the Nittany Lions will have to identify where No. 2 is at all times in their opponent's up-tempo offense.

"You have to understand on every single snap where he is," Penn State coach Bill O'Brien said. "Here is a guy that Northwestern is doing a great job with, of putting him in position to make plays. He's a very bright guy. In order to play quarterback and receiver in the same game, you have to be a very smart, instinctive football player. He'll be a huge challenge for us."

Colter played off the charts last week in the Wildcats' 44-29 win over Indiana. He rushed 14 times for 161 yards and four touchdowns and caught nine passes for 131 yards, accounting for 292 of the team's 704 total yards in the game.

All right, so he also threw an interception, but he was totally involved and creating havoc, a routine he hopes to duplicate Saturday.

"I feel like I've just got to go out there and make plays," said Colter, who lives in Denver. "Of course, I'd like to be known as a quarterback, and I've started the first four or five games there [this season]. But at the same time, there might be a situation where I have to go play receiver or play something else.

"So whatever somebody wants to call it, I'm not too worried. If they want to call me an athlete, that's fine. But as long as I'm out there making plays and helping this team out, I'll let others worry about what to call me."

Wildcats coach Pat Fitzgerald had planned to redshirt Colter during his first season because the player had suffered a torn labrum (shoulder cartilage) in his senior year of high school. But after he lost quarterback Dan Persa at midseason, the coach burned Colter's redshirt and played him in three games, including the TicketCity Bowl, in which Colter rushed for 105 yards.

Colter's role has expanded since then. Fitzgerald and his staff continue to try to find new ways to use him in an offense that has averaged 82 plays per game to date.

"He's an incredibly unselfish guy," Fitzgerald said. "He does a lot of things very, very well. I think the best part of Kain is his character. He's just a special young man. He's such a competitor, and he absolutely loves to play the game."

Fitzgerald started moving Colter around last year; he caught a 12-yard touchdown pass in a 2011 loss to Penn State. Colter is glad the coaches have stuck to the plan.

"I was going to be at a whole bunch of different positions [last year], and we were pretty efficient," he said. "We racked up a lot of yards with it, and it's worked again so far. So if it's not broke, don't fix it."

Colter said he has taken notes while watching the success of multiple-position stars in the NFL such as former Pittsburgh Steelers Antwaan Randle El and Kordell Stewart, the latter a college teammate at Colorado of Colter's father, Spencer.

"I like Antwaan Randle El a lot," he said. "He's a guy that I try to take little pieces from his game and try to incorporate them into mine. Guys like him and Kordell Stewart were able to do a lot of things that many people couldn't do. That's what made them unique. I try to take little aspects of their game . . . but at the same time, I try to be my own player."

Or three, as the Penn State defense will realize Saturday.