Ohio State made a significant jump in the AP poll this week after some top teams suffered letdowns. Purdue now has the same opportunity, although it doesn't necessarily need to rely on another team to come up with an upset.

The fourth-ranked Buckeyes look to win their 24th straight regular-season game when they face the 23rd-ranked Boilermakers in a matchup of undefeated Big Ten teams Saturday.

Ohio State (5-0, 2-0) beat Minnesota 30-7 last Saturday and rose four spots in the poll thanks to losses by seven of the top 13 teams in last week's rankings.

Purdue (5-0, 1-0), meanwhile, would almost certainly vault into the top 10 with a win over the Buckeyes. The Boilermakers, who have the lowest ranking among undefeated teams in the poll, will be trying to start 6-0 for the first time since winning all nine of their games in 1943.

"We're going to be playing an outstanding Ohio State team," Purdue coach Joe Tiller said. "It's going to take every ounce of energy we have to have some success against them."

The Buckeyes have been efficient on offense and dominating on defense. They took advantage of Minnesota miscues and didn't let up on the road to extend their school-record regular-season winning streak to 23.

Ohio State had another outstanding game on defense, holding the Gophers to minus-2 yards on 13 second-half carries. The Buckeyes lead the Big Ten in scoring defense at 7.2 points per game.

"I think we're getting after it a lot more than we did last year," said Ohio State cornerback Malcolm Jenkins , who is tied with linebacker James Laurinaitis for the team lead with two interceptions.

With their defense playing so well, the Buckeyes haven't needed much on offense. Ohio State, though, is averaging 40.3 points in its last three games.

Quarterback Todd Boeckman leads the Buckeyes offense. He isn't as dynamic as his predecessor, Heisman Trophy winner Troy Smith , but has made smart decisions and is accurate.

Boeckman has completed 69 percent (37-of-54) of his passes for 549 yards with eight touchdowns and one interception in his last 10 quarters, and has been sacked only once in his last three games. His favorite target has been Brian Robiskie , with the pair connecting on six passes of more than 25 yards - five of which were touchdowns.

Robiskie has 25 receptions for 530 yards and six touchdowns. He made an acrobatic catch against Minnesota, stealing a pass from a defender that became a 52-yard touchdown in the second quarter.

Ohio State may find that its scoring opportunities will open up in the second half against Purdue. The Boilermakers' defense hasn't allowed a first-half touchdown since the season opener against Toledo, but has given up at least three in the second half the past three weeks.

Purdue will likely need to play well in both halves to remain unbeaten. The Boilermakers had a 23-0 lead at the half before defeating Notre Dame 33-19 on Saturday.

Ohio State coach Jim Tressel, though, knows Purdue will be ready to play perhaps its biggest game of the regular season.

"They don't get rattled," Tressel said. "They come out, obviously very prepared for every game and get after it. If the game all of a sudden tightens a little bit, you can see that doesn't affect them because they've been there and had those experiences."

Ohio State has yet to face a quarterback as good as Purdue's Curtis Painter , who has completed 67 percent of his passes for 1,542 yards and 18 touchdowns, with just three interceptions.

Dorien Bryant has benefited most, leading the team with 40 receptions for 450 yards and four touchdowns. He caught eight passes for 82 yards against Notre Dame.

Kory Sheets has complemented Painter and Bryant by giving the Boilermakers a consistent ground game, rushing for 531 yards and five touchdowns on 89 carries. Jaycen Taylor has been dangerous as Sheets' backup, averaging 7.0 yards per carry.

Ohio State leads the series with Purdue 35-12-2. This is the teams' first meeting since Nov. 13, 2004, when the Boilermakers won 24-17 at home.

These teams have met seven times when they have both been ranked, with Ohio State holding a 4-2-1 edge in those games.