ANN ARBOR, Mich. – Jim Harbaugh couldn't have asked for a much better start to the 2017 season, as Michigan sits at 4-0 heading into the bye week.
As a whole, Michigan has been very impressive, especially on defense. There have been some bright spots on offense, but the unit has a lot of room to improve.
Here are grades for each position group through four games.
It hasn't been a smooth ride for the Michigan passing game, and while that was expected because the wide receivers are young, they haven't been the problem.
Wilton Speight struggled with inconsistency during the first three games before getting hurt at Purdue. It started with a pair of pick-sixes against Florida and carried over into accuracy problems against Cincinnati and Air Force.
At times, Speight looked like his old self, completing beautiful deep balls to Nick Eubanks against Florida and Kekoa Crawford against Cincinnati. When the field got shorter, the offense faltered with Speight, as Michigan scored one touchdown on 10 red zone appearances.
John O'Korn put on a show when he took over in the first quarter against Purdue. He was very accurate, completing 18 of 26 passes for 270 yards, and didn't miss any easy throws.
Running backs: B-
Michigan didn't run the ball exceptionally well last season and, surprisingly, this season has been worse on a yards-per-carry basis.
Despite Ty Isaac's 6.2 yards per carry, the Wolverines are gaining just 4.3 yards per carry as a team. Isaac's injury didn't help, as he was limited to just 20 yards on 10 carries against Purdue.
But there's major hope for this unit, especially with Chris Evans breaking out for 97 yards and two touchdowns on 14 carries against the Boilermakers. Evans was Michigan's most dynamic running back last season, and had yet to get into a rhythm before last week.
Isaac and Evans compliment each other well as Michigan's top running back duo, and with Karan Higdon also in the mix, it's a unit with upside.
Wide receivers: B
The wide receivers are difficult to grade because it's been so hard for Michigan to get them the ball, but overall, they've been mostly reliable.
Tarik Black was the best of the bunch before suffering a foot injury, but Michigan still has options. Grant Perry stepped up in Black's absence and became a critical third-down target against Purdue, while Donovan Peoples-Jones became the home run threat.
Slow starts from Eddie McDoom and Crawford haven't helped, but it looks as if the group is maturing.
Tight ends: A
The offensive group that has been most impressive this season is the tight ends, which came into the season as a relative unknown.
Michigan's 2017 wide receiver class came in with the most fanfare, but the 2016 tight ends have stolen the show. Sean McKeon and Nick Eubanks were members of that class, which 2015 quarterback commit Zach Gentry joined with a position change.
The trio has combined for 18 catches and 300 yards. Michigan only has 892 total receiving yards this season, so tight ends have made up a huge chunk of the production.
McKeon and Gentry seem to be O'Korn's favorite targets, so if he takes over the offense, they could see even more passes.
Offensive line: C
Michigan's offensive line is loaded with talent, but that hasn't been visible so far this season.
Some of Michigan's struggles in the running game have to be attributed to the offensive line, but the major concern is in pass blocking. Last week against Purdue, which was last in the nation with one sack in three games, Michigan gave up four sacks and eight tackles for loss.
The right tackle position has been especially problematic, and O'Korn had to escape the pocket several times to avoid untouched blitzers.
Mason Cole, Ben Bredeson and Patrick Kuglar are solid options, but the young right side still needs to improve. There's no reason to believe it won't, as Harbaugh brought several good linemen to Ann Arbor.
Defensive line: A
All the recent national champions in college football were built around dominant defensive lines that can stop the run and rush the passer.
That's exactly what Michigan has. Chase Winovich is leading the way with 7.5 tackles for loss and 5.5 sacks through four games. Purdue felt his wrath last week, as he made eight tackles, including 2.5 sacks.
Winovich was good as a rotational player last year. He's been excellent as a starter.
On the other end, Rashan Gary is quietly having a nice year, though he's only registered one sack. There's so much focus on Gary that Winovich and Maurice Hurst have an easier time getting into the backfield.
Hurst is a first-round NFL talent, and he's been the third-best player on Michigan's defensive line.
It's not easy to play linebacker in Don Brown's defensive scheme, but Devin Bush and Khaleke Hudson fit right in.
Michigan fans knew what to expect from Mike McCray, who's solid across the board in defending the run and can rush the passer when called upon. But the other two starters came in with little experience at the college level.
Clearly, that hasn't mattered. Bush might be the best player on the team, and Hudson has been invaluable in the VIPER role.
Bush leads the team with 33 tackles and four pass break-ups, and he trails only Winovich with 4.5 sacks and 5.5 tackles for loss.
Hudson, meanwhile, does it all. He can deliver a huge hit on a running back or drop into coverage and bat down a pass. Hudson has made 17 tackles and has 2.5 sacks and three pass break-ups.
Other than a few exceptions against Cincinnati, Michigan's young cornerbacks have done an excellent job sticking with their matchups, though they haven't faced a vaunted passing attack.
Lavert Hill has been everything Harbaugh hoped for as the No. 1 cornerback. He's received a bit of the Jourdan Lewis treatment: His stats don't stand out because quarterbacks don't often throw at him.
David Long and Brandon Watson have done a nice job behind Hill. Long has been beaten a couple of times, but his man-to-man coverage skills are better than expected as a first-year starter.
Watson is especially good at defending the deep ball, as he's knocked down multiple passes that were on target for big gains.
This position was a major area for concern coming into the season, but Michigan's defensive coaching staff showed why it's one of the best in the country.
The safeties weren't as great a concern as the cornerbacks, but they've been just as impressive.
Tyree Kinnel has morphed into the leader of the secondary, making plays against the run and providing support for his young cornerbacks over the top.
Josh Metellus is the kind of huge hitter Michigan hasn't seen at the safety position for years. He isn't as good as Kinnel in coverage, but Metellus is a big reason Michigan hasn't given up big running plays.
Special teams: B
Harbaugh has fixed most of Michigan's problems on special teams recent weeks, and if it weren't for the mistakes against Florida and Cincinnati, this group would get an A.
Quinn Nordin is 11 for 13 on field goals, including successful kicks from 49, 50 and even 55 yards. Since his two misses against Florida, he's a perfect 7/7.
James Foug has done his job on kickoffs, and Bradley Robbins took over as the starting punter against Purdue.
Peoples-Jones is the X-factor. His potential as a punt returner is similar to that of Jabrill Peppers, if he can settle into the position.