Aaron Bummer to IL, Jake Burger to Triple-A Charlotte as White Sox activate Yoan Moncada, Joe Kelly

The White Sox activated third baseman Yoan Moncada and right-handed reliever Joe Kelly from the injured list Monday and put left-handed reliever Aaron Bummer on the 10-day IL, retroactive to Saturday, with a strained right knee.

They also optioned Jake Burger, who played 21 games at third base in Moncada’s absence, to Triple-A Charlotte. Danny Mendick, who can play three infield positions and the outfield, provides more defensive versatility than Burger, who was batting .239/.276/.352 with two home runs and two doubles in 77 plate appearances. Burger had four hits in his last 24 at-bats.

Regarded as the Sox’ top left-hander out of the bullpen, Bummer experienced a bumpy start this season with a 4.91 ERA and eight walks in 11 innings. He hasn’t allowed a run or a walk in his last four appearances, however, including his most recent outing Friday against the Red Sox in Boston when he suffered what he called a minor strain in the knee.

‘‘I was starting to throw the ball a lot more the way I wanted to in the last four outings,’’ Bummer said. ‘‘It’s unfortunate timing in that aspect because I really wanted to build off those last four.’’

Bummer said he felt better Monday than he did Sunday and doesn’t expect to be out beyond the IL term. He’ll work on his craft during that time, he said.

Rookies Bennett Sousa (4.82 ERA in 12 appearances) and Tanner Banks (1.29 ERA in eight appearances) now are the only lefties in the bullpen. Sousa recorded one out for his first career save Sunday.

Welcome back

Moncada, who strained an oblique muscle on his right side before the Sox’ final spring-training game April 5, batted second Monday. He was 7-for-22 with two homers during his rehabilitation assignment at Charlotte.

‘‘Switch-hitter, he can run, work an at-bat, start a rally, add to it or finish it,’’ manager Tony La Russa said. ‘‘In the second spot, he breaks up the right-handers. I don’t feel like there is a matchup that gives him a problem.’’

Moncada should provide a boost against right-handers for an offense batting .216/.266/.332 against them.

Kelly was available for his season debut Monday, but the Sox won’t push him into back-to-back appearances just yet. He made three hitless appearances at Charlotte, striking out three in three innings.

This and that

Outfielder/designated hitter Andrew Vaughn (bruised right hand) had ‘‘his most positive day where he was able to get some work that closely resembles real swings and not holding back,’’ La Russa said. ‘‘So it’s a step in the right direction.’’

Vaughn is eligible to come off the IL on Thursday, but he might need more time. If he needs at-bats at Charlotte, it might be only two days’ worth, general manager Rick Hahn said.

• Veteran right-hander Johnny Cueto will make another start at Charlotte, which means right-hander Vince Velasquez will start Wednesday on regular rest. The Sox previously hadn’t named a starter for that day.

•  Right-hander Lance Lynn (knee surgery) is on target to return in early June, Hahn said.

• Yasmani Grandal was the DH on Monday, with Reese McGuire starting at catcher for the 15th time. Grandal has caught 13 games.

‘‘We want to make sure he’s able to sprint through the finish line, ideally in October,’’ Hahn said of Grandal. ‘‘It’s part of the reason we brought in a guy with Reese who is able to lighten some of that load.’’