West Lafayette, Ind. ? With less than three minutes to play and Wisconsin trailing Purdue by three points, Badgers cornerback Scott Starks suddenly had the game sitting at his feet.

Starks returned a fumble by Purdue quarterback Kyle Orton 40 yards for a touchdown to lift 10th-ranked Wisconsin to a 20-17 win over No. 5 Purdue.

The Boilermakers (5-1, 2-1 Big Ten) were clinging to a 17-14 lead when Orton, a Heisman Trophy hopeful, took a naked bootleg and lunged for a first down. Starks hit Orton low and safety Robert Brooks hit him high, forcing the fumble.

Starks scooped up the loose ball and sprinted to the end zone with 2:36 to play, capping a stunning comeback for the Badgers (7-0, 4-0), who have started the season with seven straight wins for just the second time since 1912.

“If the ball would’ve been bouncing around, I probably would have just covered it,” Starks said. “But it was just sitting there. I saw the perfect opportunity there.”

The play was reviewed, and replays showed the ball was out before Orton’s arm hit the ground.

“I’ve been in this racket for a long time,” Wisconsin coach Barry Alvarez said. “And I’ve never been part of a game like this.”

No. 1 USC 45,

No. 15 Arizona State 7

Los Angeles — Top-ranked USC took command early against Arizona State and routed the 15th-ranked Sun Devils. ASU (5-1, 2-1 Pac-10) was the third straight unbeaten opponent to challenge USC (6-0, 3-0). Stanford and Cal extended the Trojans, losing by a combined nine points. But the Sun Devils presented no such challenge, trailing 42-7 at halftime. Matt Leinart was 13-of-24 for 224 yards with no interceptions.

No. 4 Auburn 38, Arkansas 20

Auburn, Ala. — Jason Campbell passed for a career-high 297 yards and three touchdowns to lead Auburn. With Campbell completing 17 of 19 passes — all in the first three quarters — the Tigers (7-0, 4-0 SEC) won their ninth straight game and lived up to their highest ranking in 10 years.

No. 7 Florida State 36,

No. 6 Virginia 3

Tallahassee, Fla. — Wyatt Sexton completed 20 of 26 passes for 275 yards and a touchdown to help Florida State (5-1, 3-1 ACC) rout Virginia (5-1, 2-1). Sexton has completed 66.1 percent of his passes for 846 yards and five touchdowns since replacing Chris Rix as the starter last month. Florida State snapped a string of six straight losses against top-10 opponents.

No. 8 California 45, UCLA 28

Berkeley, Calif. — Geoff McArthur caught two of Aaron Rodgers’ career-high four touchdown passes, and California racked up 550 total yards. J.J. Arrington ran for a career-best 205 yards and two scores.

No. 12 Georgia 33, Vanderbilt 3

Athens, Ga. — David Greene passed for two touchdowns in the third quarter and ran for another in a Georgia (5-1, 3-1 SEC) rout.

No. 13 Tennessee 21, Mississippi 17

Oxford, Miss. — Tennessee’s Erik Ainge shook off a costly interception to hit Bret Smith with the winning touchdown with 6:58 to play. The Volunteers (5-1, 3-1 Southeastern Conference) scored on their first two possessions and remained in control in the Eastern Division with their 11th straight win over Ole Miss.

No. 14 Michigan 30, Illinois 19

Champaign, Ill. — Michael Hart rushed for 234 yards, and Michigan (6-1, 4-0 Big Ten) rallied from a halftime deficit, sending the Illini (3-4, 0-4) to their 12th consecutive conference loss.

Michigan State 51,

No. 19 Minnesota 17

East Lansing, Mich. — Michigan State’s Drew Stanton passed for 308 yards and ran for 102 more, setting a school record for total offense. The win kept bowl hopes alive for the resurgent Spartans (4-3, 3-1 Big Ten). Minnesota (5-2, 2-2) has lost two straight. Michigan State gained 407 yards in the first half, a school record, while taking a 31-10 lead.

No. 21 Boise State 45, Tulsa 42

Tulsa, Okla. — Antwaun Carter scored on a two-yard run with 1:24 left, and Tyler Jones kicked a 46-yard field goal with three seconds left, rallying Boise State (6-0, 3-0 Western Athletic Conference) to its 17th straight victory — the longest winning streak in the nation.

No. 22 Florida 52, Middle Tennessee 16

Gainesville, Fla. — Chris Leak threw three touchdown passes, and DeShawn Wynn scored three times for Florida (4-1). Leak completed 17-of-22 passes for 316 yards against the Blue Raiders (2-4).

Alabama 27,

No. 24 So. Mississippi 3

Tuscaloosa, Ala. — Kenneth Darby rushed for 197 yards and scored two touchdowns to lift Alabama to its first win against a ranked opponent in nearly two years. Southern Miss (4-1) had been averaging nearly 29 points per game, but the Golden Eagles never got untracked against Alabama (5-2).

Iowa 33,

No. 25 Ohio State 7

Iowa City, Iowa — Drew Tate passed for three touchdowns and ran for another to hand Ohio State its third straight loss. Iowa (4-2, 2-1 Big Ten) held Ohio State’s inept offense to 27 yards rushing and 177 total yards in beating the Buckeyes for just the fourth time in 42 years. Ohio State (3-3) is 0-3 in the Big Ten for the first time since 1988.