Michigan sophomore linebacker Desmond Morgan looks on suffering an injury during the spring game at Michigan Stadium on Saturday.

Melanie Maxwell I AnnArbor.com

It took one series Saturday for the injury bug to strike the Michigan football team.

Sophomore linebacker Desmond Morgan limped off the field following the first possession of the club's controlled scrimmage portion of the annual spring game at Michigan Stadium.

Morgan spent the remainder of the afternoon on the bench, with his right leg propped up.

"He got hit," Michigan coach Brady Hoke said, declining to go into further detail of the injury.

The 6-foot-1, 220-pound sophomore made 63 tackles in 12 games last season, including seven starts.

Despite playing without one of its top linebackers for most of the afternoon, defensive coordinator Greg Mattison said the injury allowed more time for true freshmen Kaleb Ringer and Joe Bolden, something that isn't all bad in the end.

Ringer and Bolden are early enrollees. The rest of their 2012 recruiting class will arrive on campus this summer.

"We're going to be a defense where if you lose one or two guys, at this point, before the freshmen get here, you're going to fall off a little bit," Mattison said. "I think that's what happened when Dez was out of there. I mean, that's a key guy for us, but it's forced us to put a younger 'backer, where you know we need a lot of help, under the microscope, and when we watch his tape, we're going to know exactly how he did."

Morgan wasn't the only player to end Saturday with an injury, though, as sophomore receiver Jerald Robinson suffered an ankle sprain midway through the afternoon.

Robinson's injury was not believed to be anything serious, however.

"I'm good just a lil tweak," Robinson tweeted after the game.

Senior inside linebacker Kenny Demens was active Saturday despite being restricted by a cast on his left hand.

Demens -- who also fought through a concussion earlier this spring -- said he suffered a "sprain" to his left thumb earlier in spring, but isn't overly concerned about it.

"It's a thumb (injury), it's not too big of a deal, just a sprained thumb," he said. "Hopefully hopefully I can take (the cast) off when I leave here (today)."

Mattison also said that linebackers Mike Jones (hamstring) and Brandin Hawthorne (elbow) also fought through injuries this spring.

Nick Baumgardner covers Michigan sports for AnnArbor.com. He can be reached at 734-623-2514, by email at nickbaumgardner@annarbor.com and followed on Twitter @nickbaumgardner.