Jon Gruden, the former NFL coach and current ESPN analyst, said no one can question Michigan coach Jim Harbaugh's track record in the NFL.
Gruden, appearing on an ESPN pre-NFL draft conference call Tuesday, was asked whether Harbaugh is a better college coach than NFL coach. Harbaugh, in his first season as Michigan's coach, returned to his alma mater after four seasons coaching the San Francisco 49ers.
One of Harbaugh's former players in San Francisco, Alex Boone, offered a scathing evaluation of Harbaugh during an HBO "Real Sports" piece that will air Tuesday night at 10 p.m.
Boone, who had been a vocal supporter of Harbaugh's, according to reports last December, said the coach wore out his welcome with the 49ers and pushed players too hard.
"And you're like, 'Dude, we got over the mountain. Stop. Let go,'" Boone said to HBO. "I think he pushed guys too far. He demanded too much, expected too much. And you'd be like, 'This guy might be clinically insane. He might be crazy.'"
Boone told HBO he believes Harbaugh is a better coach for college players than the NFL.
"I try not to get into Alex Boone's comments because I haven't heard any of them," Gruden said Tuesday. "I think Harbaugh has proven he's a very good coach at the NFL level. How are we going to dispute that?
"Now, I don't know who the best guards are. I don't know what Alex Boone is trying to do with this, but if you ask me, I think Harbaugh has proven he's an outstanding NFL coach (to) get to three straight NFC championship games. So I think that speaks for itself."