Slowly, Kirk Ferentz has come around.

Unlike many Hawkeye fans, the 14-year head coach wasn’t ready to declare Mark Weisman a savior after the sophomore burst onto the scene against Northern Iowa. He wasn’t even totally convinced after a 217-yard follow-up effort in a loss to Central Michigan.

He is now.

“After one game, you’re kind of like, ‘Hmm, hope I’m seeing it right,’ ” Ferentz said. “Then after two, you start thinking this guy might not be bad. After three games, I think a lot of us are starting to think maybe this guy is a running back.”

The story of Mark Weisman has grabbed the attention of Hawkeye Nation — and the rest of the nation, for that matter — over last three weeks. He went from obscurity to superstardom overnight. He literally throws defenders to the ground when they get in his way.

It’s easy to forget that Weisman is still, technically, an injury replacement.

Ferentz said on Sept. 25 that Bullock is “making progress” in recovering from a concussion he suffered against UNI. True freshman Greg Garmon has returned from an elbow injury. And indications are that Jordan Canzeri, who tore his ACL in the spring, will be on the field sooner than expected.

Weisman is only taking carries because of injuries to those players. As they all return to health, Iowa will need to decide how to adjust its backfield rotation. The answer seems pretty obvious: It shouldn’t.

Weisman trucked through Northern Iowa and Central Michigan defenders in his impressive first two starts. The only question left was how much of that was explained by weak tackling from small-school opponents.

Big Ten play started this past weekend, and Weisman had 100 rushing yards after one quarter of it.

Iowa could still use Bullock as a change of pace to Weisman. Bullock is faster and shiftier in the open field, and he is a better receiver out of the backfield. Putting the two of them in the backfield together could give the Hawkeyes some interesting options.

But Weisman almost literally couldn’t have done more this month to make his interim job a permanent one. He has carried an otherwise-weak offense on his shoulders for three-consecutive weeks. And in his first two running-back appearances — Iowa gave him only five second-half carries against the Gophers — he seemed stronger and more punishing as the game wears on.

Weisman doesn’t seem to need a complementary back to spell him. He doesn’t need to be part of a running-back committee. You even started to wonder last week why the Hawkeyes would ever do anything but run him off tleft tackle. That will remain the case even when Bullock and Canzeri are available.

Ferentz said last week it “depends what happens” on whether Weisman would move back to fullback. But then he watched Weisman rumble for 155 first-half yards against Minnesota and came to the same conclusion as the rest of us.

“His fullback days may be numbered,” Ferentz said. “He may be retiring from that spot.”