The Wolverines dominated the first half, and their defense was largely impenetrable throughout, as they defeated the Cougars, 31-0, before 108,940 on a brilliant Saturday afternoon at Michigan Stadium.
It was Michigan's first victory over a ranked team since it defeated No. 14 Notre Dame, 41-30, in 2013 and the program's first shutout since it defeated Illinois 45-0 in 2012. It was the first time BYU was held scoreless since a loss to Utah in 2003. Michigan is 3-1, BYU is 2-2.
Jake Rudock, the graduate transfer quarterback from Iowa, had his best showing so far, with two touchdowns rushing and one passing, a 4-yard throw to Amara Darboh. Rudock led the Wolverines to scores on five of their first six possessions. The highlight was tailback De'Veon Smith's physical 60-yard touchdown run.
"I thought he was having fun," Harbaugh said of Rudock. "He was playing the game, letting it rip."
Rudock had 33 yards on 10 carries, including touchdowns of 3 and 17 yards. It was his first turnover-free game of the season.
"You want to cut down on turnovers, be smart with the ball, having your feet as another check-down opportunity," Rudock said. "The way they were rushing and the way our offensive line handed it and our backs came up blocking them, you saw some creases you could slide to."
Smith left the game in the third quarter with an injury to his right ankle and was wearing a protective boot after the game. He described himself as a "little banged up" but Harbaugh said X-rays were negative. Smith said he expects to play next week at Maryland in the Big Ten opener.
A week earlier, tailback Ty Isaac scored on a 76-yard touchdown run.
"'Just wow, can this happen again? Can we get another plus-50-yard run for a touchdown?'" Harbaugh said when asked his reaction to Smith's run. "Those don't happen maybe once a season. They don't occur that often. And then to see the second, the third, the fourth, the fifth, the sixth effort, spinning, just churning, heck of a job.
"It's nice to see our backs hungry to do that and not wanting to go down. All our running backs are really got that mind-set right now. They're not looking to go down, they're looking to stay up and break tackles and get more yards and protecting the football, it's all really good."
While the offense put on a show in the first half, the defense was simply menacing from start to finish. During a stretch from the second quarter until midway through the third, BYU had six three-and-outs. It had seven for the game. BYU was 4-of-15 on third downs and punted on its first 11 possessions.
The Cougars entered the game averaging 432.3 yards a game but were held to 105 yards by the Wolverines. Their 50 rushing yards was their lowest output since 2011 when Utah held them to 11.
"By far the best team we've played in the four games," BYU coach Bronco Mendenhall said after the game. "They're a big, physical, tough football team. The strategy is sound, the execution is good. They have enough players to get the matchups they want. They're asking their quarterback just to do enough in the right settings, and they can rely on their defense while all that happens."
Michigan was favored, but the rout of the nation's No. 22 team could mean the Wolverines' return to the national rankings when they're released Sunday. The Wolverines last appeared in the AP poll on Oct. 25, 2013, when they were No. 23. They finished that season with two losses in their final three regular-season games and, obviously, out of the Top-25.
Many looked at this matchup as a key measuring-stick game for Michigan after consecutive victories against lesser opponents, Oregon State and UNLV. BYU entered coming off a 24-23 loss at UCLA last Saturday, but behind freshman quarterback Tanner Mangum, the Cougars had stunning back-to-back victories on Hail Mary throws in their first two games.
Mangum was 12-of-28 for 55 yards and took three sacks by Michigan's Mario Ojemudia, Maurice Hurst Jr. and Willie Henry. He was 0-for-4 until his first completion, which looked like Channing Stribling's second interception in two games. The ball deflected off Stribling into the hands of Devon Blackmon who converted on third and 12.
Meanwhile, the Wolverines, who were scoreless in the second half, had 448 yards. They had 131 yards in the second half.
Harbaugh wants this offense to control the clock and that's what the Wolverines did. Three of the five first-half scoring drives each went 10 plays and consumed just more than 14 minutes. For the game, Michigan had the ball for 38:38.
Through four games, Harbaugh said he can't assess everything about the Wolverines except that he understands them.
"I can't really gauge that too much," Harbaugh said when asked how much they've improved since an opening-season loss at Utah. "I'm starting to know this team and what stands out the most. They like to work. They like to work during the week. It's a good, fun team to coach, because they come out and work every day."