Auburn received a blow to its defense Wednesday afternoon when head coach Hugh Freeze announced starting linebacker Austin Keys will be out for “a while” after undergoing surgery for a thumb injury he picked up during the UMass game.

Freeze was asked about Keys’ status during his time on the weekly SEC conference call with reporters Wednesday after the Ole Miss transfer was not seen on the field during an open window of practice Tuesday evening. On Monday, Freeze noted Keys in a list of players dealing with injuries, but did not indicate what the injury was.

Dr. Nick Rachel who specializes in hand surgeries working at The Orthopedic Group in Mobile said while he can’t comment on Keys’ specific injury, when he has football players with thumb surgeries similar to what he imagines Keys had, they are often back within 6-8 weeks.

Rachel said he works frequently with high school football players who have tears or fractures in their thumb and they typically are able to be back within the same season.

Generally, the recovery process includes a heavily protected hand for the first 4-6 weeks after the surgery and then working back into full training when that cast comes off.

Depending on the severity of the injury and Keys’ recovery timeline, Rachel said linebackers could wear a “club cast” on his right hand and play while he continues to get back to full strength. A cast like that, of course, would limit his ability to make plays on the ball while he is in coverage over the middle of the field.

A four-week return after the UMass game would be roughly around Auburn’s SEC home opener against Georgia on Sept. 30. Six weeks would put Keys out until Auburn’s Oct. 14 trip to LSU. The bye week between Georiga and LSU is timely for his recovery. And an eight-week recovery would mean a return around Auburn’s Oct. 28 game against Mississippi State.

Keys was previously dealing with a shoulder injury during the preseason, but he was named a starter on Auburn’s initial depth chart and did in fact start the game against UMass. He played 18 total snaps in the game according to Pro Football Focus.

It’s not clear exactly when the injury occurred but at points early in the second quarter Keys was seen playing with no additional or abnormal tape or wrapping on his hands.

But toward the end of the quarter, his right hand was heavily wrapped. He briefly played through the injury and started the second half, but came out in the third quarter.

Keys was brought in to Auburn from Ole Miss to be that starter at middle linebacker, which left a competition for the second inside linebacker spot — the weak side linebacker — between Larry Nixon III, Eugene Asante and Cam Riley.

Riley ultimately won that job, in part due to his ability to play both in the middle and on the edge as well as his experience as a starter for Auburn last season.

In fall camp when Keys was dealing with his shoulder injury, Nixon ended up filling that spot while Asante and Riley rotated in the other linebacker position. It was Asante who generated the most buzz coming out of the preseason, and he’d go on to lead Auburn with six tackles in the 59-14 win over UMass.

So with Keys out for the long term now, who’s next?

On the first drive where Keys was seen wearing a wrapping on his hand — a UMass possession inside the final five minutes of the first half which ended in a missed field goal — Nixon was the immediate one to take Keys position on plays where he was not on the field. Asante also came onto the field in place of Riley during that possession.

Asante would pick up a sack on a 3rd-and-4 play inside the redzone that possession which pushed UMass back before the ensuing missed field goal.

“It is real fun playing beside Eugene,” Keys said of Asante during fall camp. “He keeps the standard and he’s really one we look at as a watchman. He holds everybody accountable and you feed off Eugene. You gotta love the dude.”

Keys would take the field one more time in the first half, lining up next to Riley as UMass took a knee with four seconds remaining before halftime. He started the second half next to Riley in the middle of the field and took the field as well for UMass’s second possession of the half following safety Jaylin Simpson’s interception return for a touchdown.

Up by such a large margin, Auburn used Nixon, Asante and other backups including Jake Levant for the rest of the game. The severity of Keys injury wasn’t clear at the end of the game or even before Wednesday.

Nixon did not record a stat in Auburn’s win, but based on how Auburn lined up in practices and in the UMass game, Nixon appears the easiest to slide into Keys’ role because he’s already played it.

“The biggest concern you have when you take a transfer at linebacker that isn’t mid-year is how quickly can you pick up the defense,” linebackers coach Josh Aldridge said of Nixon during fall camp. “I wasn’t real comfortable taking one after spring unless he was a guy like Larry that had all the production and played a lot. It’s easy to install and teach him things because he’s played so much football.”

That does, however, leave the question of where Asante gets onto the field, as he’s proven to be both productive and a vocal leader. Auburn has shown that it loves to rotate its players in multiple position groups and that was likely to be true of the linebackers even with Keys in the picture.

It will remain the case without him. It wouldn’t be a shock to see all three linebackers playing in either the middle or weak-side position.

Matt Cohen covers Auburn sports for AL.com. You can follow him on Twitter at @Matt_Cohen_ or email him at [email protected]