NEW YORK -- The Yankees are preparing to proceed without Tommy Kahnle in their bullpen for the rest of this season, with Tommy John surgery having been recommended for the right-handed reliever.

Kahnle underwent an MRI on Friday in New York that revealed damage to his right ulnar collateral ligament. Kahnle was placed on the injured list prior to the Yanks' 5-1 victory over the Red Sox, and manager Aaron Boone said that the hurler is leaning toward having the surgery.

"Your heart goes out to Tommy, knowing that it's a significant injury that's got to get taken care of now," Boone said.

Kahnle, who turns 31 next week, struck out the side on Sunday against the Nationals in Washington, helping to preserve a 3-2 Yankees victory. He felt discomfort in his right forearm on Tuesday during an evening workout at Camden Yards in Baltimore and was unable to play catch prior to Wednesday's game, prompting the club to shut him down.

His absence was notable on Thursday, when Boone pushed right-hander Jonathan Loaisiga for a third inning of relief in the Yanks' come-from-behind, 8-6 victory over the Orioles.

"Missing that one big key piece in Tommy Kahnle is going to be tough for us," outfielder Aaron Judge said. "We're going to be praying for him. Hopefully the recovery goes well and everything works out for him."

Left-hander Jordan Montgomery, who underwent Tommy John surgery in June 2018, said that he would advise Kahnle to be around the team as much as possible.

"The only thing I really needed was just to be around the guys," Montgomery said. "I did my rehab here as much as I could just so I could be around everybody, because I've always heard how lonely it was. I remember when they would go on road games, how lonely it was."

Kahnle pitched to a 3.67 ERA (122 ERA+) in 72 appearances for New York last season, enjoying a bounce-back campaign after he spent much of 2018 in the Minors. Kahnle owns a 3.82 ERA in 285 career appearances for the Rockies, White Sox and Yankees since 2014.