CHICAGO -- Referring to Aaron Bummer as the White Sox setup man accurately depicts the left-hander’s important bullpen role for the upcoming 2021 season.

This depiction also sells short Bummer’s overall value in getting the baseball from White Sox starters to new closer Liam Hendriks. Look at the 27-year-old as more of a high-leverage force for a team with World Series championship goals.

“Regardless of whether it’s the sixth, seventh or eighth inning, I want to go out there and get as many outs as I can,” Bummer told MLB.com during a recent phone interview. “And I love the feeling of the leverage stuff and knowing that the game is in the balance. The game can shift one way or the other: whether it’s getting a ground ball with runners on base to get out of a jam, [or] getting a double play to end the sixth and then being able to go out there and throw the seventh.

“I kind of thrive on that situation. I trust the rest of the bullpen and I hope the coaching staff trusts the rest of the bullpen as well to go out there and get all those outs. I’m not going to sit here and say I want the eighth inning, or I want this. I’m going out there to pitch and help in any way possible.”

Bummer put together a dominant 2019 campaign, finishing with a 2.13 ERA, 60 strikeouts against 24 walks and 43 hits allowed in 67 2/3 innings (58 games). He agreed to a five-year, $16 million deal with club options for ’25 and ’26 last Spring Training and was poised to set up things for Alex Colomé.

But during a home game against Cleveland on Aug. 7 last year, Bummer’s season almost came to an end. He left after a two-out throwing error on Cesar Hernandez’s grounder back to the mound and an ensuing pitch to José Ramírez that followed a visit from the head athletic trainer in the seventh frame, but he actually felt something fairly severe in his left biceps a little earlier in the game as part of his second relief inning.

“Oh, it felt like a knife was going through my biceps,” said Bummer. “It was a feeling that I never had before. I’ve had Tommy John. I’ve had a bunch of things wrong with my elbow. I’ve gone through all those things, and this didn’t feel like any of that.

“There were two outs, and I kept kind of looking up at the radar gun seeing, ‘OK, this kind of hurts but I must be OK if my velo is holding.’ I kind of kept going, and I don’t think I made it anything worse than what it was, but kind of threw the last pitch to José Ramírez and it was definitely the smartest decision to take myself out of the game and see where I’m at.”

Bummer’s injury was more nerve-related than a strain, meaning it took a little longer to find the extent of the problem and an appropriate rehab course. He returned on Sept. 24 and made two scoreless regular-season appearances, and then he added two more scoreless efforts in the American League Wild Card Series vs. Oakland. Bummer's work to get fully healthy has continued in the offseason, with a few more boxes to check off, he said.

“It was moreso a typical maintenance program of re-strengthening my biceps and keeping on the things we were doing just to make sure, going into Spring Training, I was going to be in a great spot,” Bummer said. “There wasn’t a prescribed rehab, and it wasn’t about knocking this stuff out. It was more, let’s keep the progress going in the right direction.

“As we stand here today, I’m 100 percent full-go, ready for Spring Training. I’m in a good place.”

That good place for Bummer, whose devastating sinker has helped him produce the second-highest ground-ball rate among relievers over the past two seasons, should mean good things for the White Sox. Those good things could come in the eighth or the sixth or even across two innings, if needed.

With one of the best overall bullpens in the game, the White Sox have the luxury of using one of their best relief weapons in the toughest situations.

“If I make my pitches, I’m going to win,” Bummer said. “That’s kind of the way I feel. You have to have the confidence going out there on the mound,” Bummer said. “It doesn’t matter, right-handed or left-handed. If I make my pitches, I’m better than the other person.

“That’s the mindset that everyone in our bullpen has. Everyone trusts their stuff. Everyone trusts their ability, and when we are doing that, at the end of the day, we will have a lot of success.”