Time running short for injured linebacker Chris Galippo

USC middle linebacker Chris Galippo watched from afar — about 20 yards behind the line of scrimmage — as freshman Lamar Dawson took most of the snaps during full-contact drills the last two weeks.

Now, with the opener against Minnesota a week away, Galippo knows that he must prove his injured right shoulder is sound.

“It’s getting down to the nitty-gritty,” Galippo said Friday. “I’ve got to be able get a good week of full-contact practice.”

Galippo, a fifth-year senior, suffered a sprained shoulder early in training camp and was limited for two weeks. He participated in a scrimmage at the Coliseum last Sunday but has mostly shadowed Dawson since.

“He’s going to have to practice and be able to show us that he can go out there and play,” Coach Lane Kiffin said of Galippo. “It would be scary to put him out there having not done anything for a couple weeks. That’s why we’re really focused on getting him healthy.”

Last season, coaches installed Devon Kennard as the starting middle linebacker, pushing Galippo to reserve status and special teams. But Galippo started the last five games at middle linebacker and Kennard, who had off-season hip surgery, was moved back to defensive end when camp opened.

The 6-foot-2, 230-pound Dawson has performed well in Galippo’s absence, even intercepting a Matt Barkley pass this week.

But the Kentucky native lacks college game experience.

“There’s a lot that goes into playing middle linebacker at any age,” Kiffin said. “As a true freshman that wasn’t a midyear [enrollee], that’s a lot on him. But we feel very confident.”

Galippo is hoping to be near full strength by the opener. Better to have managed the injury in training camp, he said, than to be dealing with it throughout the season.

“The last thing you want is be lining up against UCLA in [late November] and I’m still going through this,” he said.

Awaiting word

The Trojans hope to receive a determination on defensive lineman Armond Armstead’s status by early next week.

The 6-5, 295-pound senior from Sacramento has not been allowed to practice while awaiting results of tests for an undisclosed medical condition.

Armstead can play tackle and end. If he is cleared to play, he would provide a significant boost in depth.

“Right now, we’re still one guy banged up from being in trouble there,” Kiffin said. “He would give us a big security blanket.”

Quick hits

Senior Martin Coleman worked with the first team offense at left guard. On Thursday, freshman Marcus Martin had worked at the spot. But coaches are hoping that junior Abe Markowitz (foot) will be cleared in time to practice next week and play in the opener. . . . Junior Curtis McNeal and redshirt freshman D.J. Morgan got most of the first-team reps at tailback. “They’re cranking it up a little bit,” Kiffin said of the tailback competition. “They’re competing right now for national-TV carries.” . . . Freshman defensive end Greg Townsend Jr. was cleared by the NCAA Eligibility Center and will rejoin the team for practices.

gary.klein@latimes.com

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