Purdue’s Brycen Hopkins runs in a 10-yard touchdown pass Saturday against Michigan. (Photos by Dave Deak)

WEST LAFAYETTE – Chris Evans ran for two touchdowns in the second half and backup quarterback John O’Korn rallied No. 8 Michigan from a halftime deficit Saturday to a 28-10 victory at Purdue.

Evans finished with 14 carries for 97 yards for the Wolverines (4-0, 1-0 Big Ten).

O’Korn was forced into action when starting quarterback Wilton Speight left late in the first quarter with an undisclosed injury, and the former Houston starter came up every bit as big as the Wolverines’ defense in the second half.

He finished 18 of 26 for 270 yards with one touchdown and one interception after throwing only one pass in Michigan’s first three games.

”I thought John really played great,” coach Jim Harbaugh said. ”He was seeing things really good right from the time he came into the ball game. He ran the offense well and made big plays.”

Harbaugh said only that he thought Speight’s injury was ”soft tissue” and ”not structural.”

Purdue (2-2, 0-1) rewarded its first home sellout crowd in almost nine years by jumping to a 10-7 halftime lead. But the Boilermakers managed only 10 yards of offense and one first down in the second half.

Brycen Hopkins caught a 10-yard touchdown pass from Elijah Sindelar on a brilliant misdirection play to tie the game in the second quarter.

”The second half, I think Michigan wore us down and beat us like they beat everyone. They were able to pound the football,” Purdue coach Jeff Brohm said. ”The better football team won today.”

O’Korn, meanwhile, led Michigan on back-to-back, time-consuming drives in the third and fourth quarters. Evans capped the first with a 10-yard TD run with 2:42 left in the third to make it 14-10 before sealing the win with a 49-yard scoring run with 6:46 left in the fourth.

Ty Isaac scored on a 1-yard plunge in between Evans’ touchdown runs.

The Boilermakers also lost two key defensive starters on targeting calls in the second half. Safety John Thieneman and linebacker Ja’Whaun Bentley will now miss the first half of the Minnesota game, too.

Michigan hosts in-state rival Michigan State on Oct. 7 following a bye while Purdue returns to action Oct. 7 by hosting surprising Minnesota.