It's a big weekend for the Big Ten.

Conference championship hopes are on the line when four of the league's Top 25 teams face each other Saturday. No. 13 Iowa (7-1, 4-0) travels to No. 8 Michigan (6-1, 3-0) and No. 18 Penn State (5-2, 2-2) plays at No. 4 Ohio State (8-0, 3-0).

Iowa hasn't beaten Michigan since 1990. A victory would give the Hawkeyes a legitimate shot at claiming a share of the Big Ten championship -- something they haven't done since 1990. The schedule is in their favor.

After Michigan, the Hawkeyes return home for games against Wisconsin and Northwestern before finishing at Minnesota. They do not play Ohio State this season.

"It's an important week," Iowa coach Kirk Ferentz said. "I'd be lying if I said it wasn't. Obviously neither of us have lost in the conference yet, so that adds to the significance. But there is a lot of football left here."

Michigan must find a way to stop Fred Russell, who ranks eighth in the nation with 128.1 yards rushing per game and has scored eight touchdowns. Russell, who went to high school 25 miles from Ann Arbor, signed with Michigan in 1999 but failed to meet NCAA eligibility requirements and ended up at Iowa.

Iowa also has the mobile Brad Banks at quarterback, making the offense even more difficult to stop.

"There is nothing worse than having to chase a guy sideline to sideline, getting tired and then huddling up for the next play," defensive tackle Grant Bowman said. "It's an extra dimension that is really tough to defend against."

Michigan, which rallied from a 20-7 third-quarter deficit to beat Iowa 32-26 last season, needs a win to possibly set up another showdown with archrival Ohio State for the league championship at the end of the season.

"This is a big game for us any way you look at it," linebacker Victor Hobson said. "We want to be the Big Ten champions. We know where we want to go and we know what we want to do."

Ohio State could be in the best position of all three teams. The Buckeyes have just three tough games left against Penn State, Minnesota and Michigan, and they are all at home. An undefeated season gives Ohio State a shot at playing in the Fiesta Bowl.

Running backs will be key in this game. Last week, Larry Johnson set a Penn State record with 257 yards rushing and two touchdowns on 23 carries.

Ohio State freshman Maurice Clarett has 980 yards this season and needs 146 to break Robert Smith's freshman school record.

Penn State beat Ohio State 29-27 last season, but the Nittany Lions have not beaten the Buckeyes in Columbus since 1978.

"What we are thinking about is what we got going right now," Ohio State safety Mike Doss said. "We have a big challenge Saturday and we are looking forward to it."

In other Top 25 games, it's No. 1 Miami at West Virginia, Temple at No. 3 Virginia Tech, No. 5 Georgia at Kentucky, No. 6 Notre Dame at No. 11 Florida State, No. 17 Iowa State at No. 7 Texas, No. 9 Washington State at Arizona, No. 10 LSU at Auburn, No. 15 Southern California at No. 14 Oregon and No. 19 Alabama at No. 16 Tennessee.

Also, it's No. 20 Kansas State at Baylor, Texas Tech at No. 21 Colorado, No. 22 Air Force at Wyoming, Washington at No. 23 Arizona State and Ball State at No. 24 Bowling Green.