Sandy Leon (Patrick McDermott/Getty Images)

The Nationals will call up starter John Lannan, outfielder Eury Perez and catcher Sandy Leon on Saturday when the rosters expand, Nationals Manager Davey Johnson said. Mark DeRosa, who has been on the disabled list since Aug. 5 with a groin injury, will also be activated. 

“We’re going to bring up a limited amount of guys that are going to help us win games in September,” Nationals General Manager Mike Rizzo said. “We’re not in the situation where we’re going to bring guys up to take a look at players like we have in the past. The players that we bring up are going to be players that can help us in real games for a playoff stretch.”

The second wave of September call-ups won’t happen until later, potentially after the minor league seasons end. Johnson said Syracuse outfielder Corey Brown and likely another pitcher will be added later. Brown went 3 for 16 with a home run in nine games with the Nationals this season. Christian Garcia, a flame-throwing reliever in Syracuse, is a potential candidate to be added to the bullpen. 

After a rough start to the season in Class AAA Syracuse, Lannan has pitched his best baseball of the season of late, tossing two straight complete game shutouts, striking out 12 and allowing only 11 hits. Johnson said he would add Lannan to the bullpen and have him pitch from there to stay fresh. Lannan will slide into the starting rotation for Stephen Strasburg, who has about two or three more starts left before his shutdown. Johnson said he wouldn’t use Lannan until Sept. 3, his normal schedule 

“He likes to throw long so maybe we’ll work it out with their bullpen,” Johnson said, joking. “He can throw with their bullpen and they can throw him back.”

Leon, 23, a switch-hitter known as a strong defender, went 7 for 28 (.250) in 10 games with the Nationals this season. He is hitting .346 in 19 games with Syracuse since being optioned on Aug. 4. Perez, 22, is a lightning-quick right-handed outfielder in Syracuse who is hitting .314 with 51 stolen bases across three minor league levels this season. Johnson said the Nationals liked Perez for his ability to pinch run.

Jhonatan Solano, who played in 12 games for the Nationals this season, is in Class AA Harrisburg rehabbing an oblique injury that landed him on the disabled list on July 18. Johnson said because Solano didn’t have enough at-bats there he would head to the instructional league in Florida to continue playing. 

Starter Chien-Ming Wang, who has been on the disabled list with a hip injury since July 1, is expected to make one more rehab start before returning to the Nationals, Johnson said.

DeRosa, a veteran presence who can serve as a backup outfielder or middle infielder, was hitting .152 in 34 games before his injury.

More from The Washington Post

Henry Rodriguez undergoes surgery

Aug. 31 Nationals-Cardinals lineups

Getting to know the Nats’ bullpen

Werth, Harper are a potent 1-2 punch