Michigan coordinator Don Brown discusses the defense's progress this season.


Ann Arbor — Michigan coach Jim Harbaugh knows a major reason his team is unbeaten through four weeks is defensive coordinator Don Brown.

Brown is in his second season as the Wolverines’ defensive coordinator and has guided them to the nation’s No. 1-ranked defense after the victory at Purdue last weekend — the Boilermakers were 0-for-12 on third down and had 10 yards in the second half.

Michigan is yielding 203.3 yards a game, is fourth in rushing defense (69.3) and eighth in passing yards allowed (134.0). The Wolverines also are second nationally in defensive touchdowns and first in team sacks, averaging 4.5 a game.

“Not really that important right now,” Brown said of having the No. 1-ranked defense. “I will say this, though, it’s a measuring stick to stop at the bye, pause, take a deep breath and at least it shows we’ve come out of the gates very strong and are playing at a solid level.”

Brown led Boston College to the nation’s No. 1 defense in 2015 before Harbaugh hired him to Michigan, which he led to the nation’s top-ranked defense last season.

“You look at his track record, everything he’s touched has turned to gold,” Harbaugh said of Brown during his “Inside Michigan Football” radio show.

Harbaugh joked that his daily mood is dictated by Brown.

“As long as Don Brown’s good, I’m good,” Harbaugh said earlier at his weekly Monday news conference. “You want to know my happiness is or my mood is like, Don Brown’s mood is good, I’m good.”

But Brown’s success could potentially make him attractive for head coaching jobs.

Brown, 62, after appearing on the radio show, was asked if he’s interested in becoming a head coach.

“Not now. I don’t think now,” Brown said Monday night. “I’ve got a pretty good gig, don’t I? Take a look at how young we are defensively. It’s pretty exciting isn’t it?”