Tennessee baseball coach Tony Vitello is not sure if AJ Russell will be available for the Vols during the Knoxville Regional.

Russell has battled soreness after returning from arm issues to throw twice during the SEC Tournament.

“I think that is the one guy that you don’t know exactly if he will be available or what would be available," Vitello said Wednesday.

No. 1 Tennessee (50-11) opens NCAA Tournament play against No. 4 seed Northern Kentucky (35-22) in the Knoxville Regional on Friday (7 p.m. ET, SEC Network).

Russell, who missed two months with arm soreness, threw in the opener and the title game during Tennessee's five-game run to the SEC Tournament title. He threw two innings, allowing one run on two hits with a hit batter. He struck out two.

Will AJ Russell be available for Tennessee baseball regional?

Vitello said if Russell is available for the regional, it would not be for more than an inning.

"To this point, we have probably pressed it as good as we can," Vitello said.

The 6-foot-6 Russell returned during the SEC Tournament after not throwing since March 23. He pitched. an inning in UT's 13-4 loss to Vanderbilt. He struck out two, hit a batter and allowed a hit. He started against LSU in Tennessee's 4-3 title-clinching win. He allowed a solo homer.

Vitello indicated Russell probably would not have started against LSU had it been a normal weekend series. But Russell wanted to start and had time to recover from his prior outing.

"He has been eager to compete, which obviously he has done sparingly," Vitello said. "We have tried to meet him in the middle of what is the best thing to do."

AJ Russell has battled arm issues throughout season

Russell left his second start of the season against Albany on Feb. 23 with side soreness. He did not return until March 17 against Alabama, then was injured against a week later against Ole Miss.

Russell took over Tennessee's Friday night starter spot as a sophomore. He struck out 10 in 4⅓ innings on Feb. 16 against Texas Tech, including getting the first eight outs of the game via strikeout. He allowed two runs on three hits and a walk.

PREDICTION: Why Tennessee baseball will – and won’t – win Knoxville NCAA Regional

The Franklin, Tennessee, native struck out four in three innings against Albany before leaving the game. He allowed three hits and walked one.

Russell started against Alabama in his return, striking out two and allowing one run on two hits in two innings. He struggled against Ole Miss in his last outing before departing with arm issues. He walked six, allowed two hits and surrendered four runs. He struck out three in three innings.

Russell was 2-0 with a 0.89 ERA in 30⅓ innings with 47 strikeouts as a freshman. He made 24 appearances with one start.

Mike Wilson covers University of Tennessee athletics. Email him at michael.wilson@knoxnews.com and follow him on Twitter @ByMikeWilson. If you enjoy Mike’s coverage, consider a digital subscription that will allow you access to all of it.

This article originally appeared on Knoxville News Sentinel: AJ Russell injury update: Tennessee baseball in Knoxville NCAA Regional