Ravens left offensive guard Kelechi Osemele will be placed on injured reserve and undergo season-ending back surgery, coach John Harbaugh announced today.

"He's heading to IR," Harbaugh said. "He's working right now with the doctors and his representative to find what type of surgery he wants to do and what's the best person to do it."

Harbaugh expressed optimism that Osemele could recover in three to four months and return in time to participate in the offseason program.

A.Q. Shipley is expected to continue starting at left guard.

"A.Q. is a pit bull," Harbaugh said. "He's a fighter in there. He's smart. He knows what to do and he plays with good technique. We're pleased with the way he played."

Osemele's roster spot could go to Ravens cornerback Asa Jackson.

Jackson has served an eight-game suspension for violating the NFL performance-enhancing drug policy and is eligible to be activated from the reserve-suspended list.

The Ravens could be granted a roster exemption for Jackson as they determine his level of conditioning. Jackson has been training in Arizona while completing his league-mandated punishment.

"We're going to take a good look at him this week," Harbaugh said. "We'll see where he's at. Asa says he's been working hard and he's in great shape. Hopefully, he's in that kind of shape where he can slide right in there and help us. We'll see if he can help us this week. I'm not ruling that out as a possibility."

Jackson was suspended for unauthorized usage of Adderall, the second time he's run afoul of the NFL policy.

Meanwhile, starting cornerback Jimmy Smith was "feeling better today" after suffering a groin injury that forced him out of the Ravens' 24-18 loss to the Cleveland Browns. He was replaced in the lineup by Chykie Brown.

"He had a little groin strain in there," Harbaugh said. "We felt like it was better for Chykie to play during the game, the trainers did. We'll keep working on that throughout the course of the week and see how that develops."

awilson@baltsun.com

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