Iowa Hawkeyes running back Damon Bullock (right) gets a block from teammate Iowa Hawkeyes offensive linesman Brett Van Sloten (center) on Northwestern Wildcats defensive lineman Sean McEvilly (left) during the second half of their NCAA game at Ryan Field on Saturday, Oct. 27, 2012, in Evanston, Ill. Northwestern won, 28-17. (SourceMedia Group News/Jim Slosiarek)

EVANSTON, Ill., — The one bright spot in Saturday’s loss at Northwestern spoke about the dark place he had been in just a few weeks ago.

Iowa running back Damon Bullock suffered a concussion on Sept. 15. He was tackled from behind and his head dipped forward and slammed into a defensive back’s knee. It took 5 1/2 weeks for his return, but Bullock pumped a little juice into Iowa’s struggling offense during the 28-17 loss at Northwestern, rushing 22 times for 107 yards.

And, as it turns out, it was just in time. Mark Weisman, who’s battled a sprained ankle for the last two weeks, suffered a leg injury in the first half and didn’t return. Iowa coach Kirk Ferentz said a decision on Weisman’s status would be made sometime this week before the Hawkeyes (4-4, 2-2 Big Ten) travel to Indiana (3-5, 1-3). Bullock also boosted the passing game with five catches for 41 yards.

“Damon catches the ball so well,” quarterback James Vandenberg said. “That was a big positive for us today.”

Bullock’s description of his concussion symptoms sound absolutely dreadful.

“It was really blurry, I can’t explain it,” the sophomore from Mansfield, Texas, said. “There was a lot of not remembering stuff. It was two weeks after and I thought I was all right, but still, going to class with migraines and all kinds of crazy stuff like that.”

Bullock, who’s gone for 100 yards in two of his four games this year, was on track to return for the Michigan State game on Oct. 13, but suffered a blow to the head during practice leading up to the game.

“And I was just out of it again,” he said. “I just had to get going step by step and that was pretty much it.”

He said he felt good after Saturday’s game. That gives the Hawkeyes one healthy running back for next week’s game. Sophomore Jordan Canzeri was in uniform Saturday, but didn’t play. True freshman Michael Malloy also might be an option.

Good health is becoming as elusive as victories for the Hawkeyes, who’ll fight this week to keep from falling below the .500 mark for the first time since it pulled to even with a victory over Northwestern on Nov. 3, 2007.

Senior Matt Tobin replaced Brandon Scherff at left tackle. Freshman Jordan Walsh started at left guard, but junior Nolan MacMillan replaced him. Freshman Austin Blythe returned from an ankle injury to resume his spot at right guard.

Iowa ran out of bodies at defensive end in the second half and put true freshman Drew Ott in when senior Joe Gaglione briefly left.

“He did a good job in camp and he’s steadily improving right now,” Ferentz said. “We’ve had our share of guys coming out of the lineup right now with injuries and that type of thing. So, we thought with five games left, we thought let’s get him in the water and get him swimming a little bit. It’ll help our team right now, which is more important, but hopefully, it will help him be right in the mix of things moving forward.”

The fact that Iowa decided to play Ott, the seventh true freshman to go into the lineup this season, showed coaches are playing with the “now” and the Legends Division in mind. Nebraska (3-1) took charge with its victory at Michigan last week.

Iowa’s schedule could lead up to a two-week showdown to have a say in the Legends, with at Indiana (3-5) and playing host to Purdue (3-5) on Nov. 10 serving as lead up to at Michigan (5-3, 3-1) and a home finale against the Huskers.

You say that in one breath and then there’s the reality that this team is playing to stay above .500 this week in Bloomington.

“We’re 4-4 and we’ve lost two straight,” Ferentz said. “It’s always hard anytime you lose, but there aren’t many options. You go back to work tomorrow and get back on your feet. That’s the only choice that we have, the only option that we have.”