Jared Allen leaves practice after tweaking his ankle

MANKATO, Minn. -- At one point during Minnesota Vikings' training camp on Tuesday, Everson Griffen had replaced Pro Bowler Jared Allen, second-year linebacker Audie Cole was filling in for Erin Henderson and special teamer Andrew Sendejo was at safety for Harrison Smith.

Once enjoying a relatively healthy training camp, Minnesota is now dealing with a few injuries along its defense. But as several players sat out Tuesday afternoon's padded practice, many are being held out for precaution, according to Vikings coach Leslie Frazier.

Allen's left ankle injury drew the most concern Tuesday as he left midway through practice and was attended to by the team's medical staff. Frazier said Allen "tweaked" his ankle a little bit and the team was trying to determine if he would need an MRI on the ankle.

Henderson has been bothered with a sore groin and was held out Tuesday. Frazier said Harrison Smith "twisted" his knee, though Smith did stay on the field for the rest of practice and jogged off afterward.

"We held some other guys out to get them a day of rest in preparation for our Friday game, so we'll see how they do tomorrow," Frazier said. "So we'll see how those guys progress over the 24 hours and whether or not we'll give them a shot in the ball game on Friday."

Frazier said Allen was one of a few players unlikely to play in Friday's preseason game anyway.

"He wasn't going to see any action anyway," Frazier said. "I can definitely say that, especially in light of this situation."

Linebacker Desmond Bishop has missed three full days of practice with a sore groin. Defensive tackle Christian Ballard missed his first action with a groin injury as well.

The secondary has been hit hardest with Smith joined on the sidelines by cornerbacks Xavier Rhodes (hamstring) and A.J. Jefferson (ankle). Cornerback Josh Robinson and safety Mistral Raymond both have returned to practice after dealing with hamstring injuries themselves.

Frazier said Rhodes could return Wednesday, possibly putting him in line to play Friday. Smith's jogging seemed to indicate his sitting out was more precautionary.

"It doesn't seem (bad) just watching him move around, but you never know," Frazier said. "So they're going to check it out and make sure."

Frazier expects Henderson to return to practice on Wednesday. With Henderson and Bishop each nursing injuries, Minnesota signed veteran linebacker Stanford Keglar on Tuesday and released undrafted rookie linebacker Nathan Williams, who has been on the physically unable to perform list after offseason ankle surgery.

"Signing Stanford will help us from a depth standpoint," Frazier said. "Hopefully we'll get Desmond back here pretty soon, but I think that improves our depth. We were lacking with Nate not being able to practice, so now to have another body to practice I think that helps our depth a little bit from a practice standpoint."

Backup offensive linemen Joe Berger has missed the past two days of practice. Frazier said Berger was dealing with a loss in his family.

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