Jehuu Caulcrick has rushed for 20 touchdowns this season -- a feat that seven teams in the Big Ten still haven't accomplished.

Opponents call Michigan State's senior running back "the big guy." Standing 6 feet tall and weighing 255 pounds, Caulcrick has used his size to bully defenses all season. He and his fellow tailback, junior Javon Ringer, have combined for more rushing yards than any two teammates in the Big Ten this season.

But tomorrow, the Spartans' running backs may meet the biggest challenge they'll face in 2007, when they line up opposite Penn State's defense, which is tied for the best in the Big Ten against the run.

"We've seen some film on them, and they are a tremendous team up front," Spartans offensive tackle Mike Gyetvai said this week. "Very physical. I guess it always comes down to who runs the ball the best."

Sean Lee, Penn State's junior linebacker, was impressed with what he has seen while studying the two running backs this week.

Ringer's strength, Lee said, is his quickness and ability to bounce off defenders. The junior has averaged more than six yards per carry this season and is second in the conference in rushing yards.

Lee calls Caulcrick a "downhill" running back -- one that won't try to duck and dodge defenders, but aim for a hole in the line and get there quickly.

But the Lions have seen guys like that before. Wisconsin's P.J. Hill, boasting a 5-foot-11, 227-pound frame, was held to only 75 yards last month when the Badgers visited Beaver Stadium.

What the Lions haven't seen very often, however, is the two-pronged rushing attack that the Spartans rely on. Normally, Lee said, there's only one featured back to study.

"Coming into the game, you have to realize what they are bringing to the table and how you play against them," Lee said.

Using the combination of Caulcrick and Ringer has helped the Spartans running game stay fresh into the fourth quarter this season and control the clock.

Michigan State has held the ball longer than its opponent in four of its last five games.

That's exactly what the Lions want to avoid tomorrow.

They don't want a repeat of their Week 4 trip to Michigan -- when the Wolverines held the ball for almost 35 minutes, including almost 12 minutes in the fourth quarter alone. Mike Hart, the Wolverines' senior running back, carried the ball 44 times for 153 yards in that game.

It happened all over again against Ohio State in Week 9. The Buckeyes ran the ball 48 times and controlled the clock for almost 38 minutes.

The Lions' defense doesn't want to let the clock run out again tomorrow.

"The clock on the road is really big," cornerback Lydell Sargeant said.

"Being able to control the clock as a defense is something we take pride in."