Time to talk September recalls. The Nationals have given us a pretty good idea of who will be joining them in the coming days as major league rosters expand on Sept. 1. But the tenor of these recalls differs from years past when the competitive portion of the season was long over and an evaluation period had begun.

“We’re not in a situation where we’re going to bring guys up to take a look at players like we have in the past,” Nats general manager Mike Rizzo said. “The players that we’re going to bring up are going to be players that can help us in real games for a playoff stretch.”

Washington manager Davey Johnson said catcher Sandy Leon, outfielder Eury Perez and left-handed pitcher John Lannan will be added to the roster from Triple-A Syracuse. In addition, veteran utility man Mark DeRosa will move off the 15-day disabled list after recovering from a groin strain.

Syracuse still plays through Monday, though it has long been eliminated from the International League playoff chase. After its season ends outfielder Corey Brown will join the Nats, too. Johnson only said a reliever would be added – a power pitcher not currently on the 40-man roster. He didn’t name the player, but it’s pretty obvious that will be Syracuse closer Christian Garcia, who has been brilliant at two different levels this season.

Henry Rodriguez won’t be back. The right-handed reliever had elbow surgery on Friday and won’t be ready until spring training. He likely won’t be healthy enough to even play Winter Ball in his native Venezuela as he normally does. Meanwhile, veteran Chien-Ming Wang has one more minor-league rehabilitation start. The organization won’t say exactly what its plan is once Wang completes that start.

Quick breakdown on the players coming up: Leon will be the third catcher. He has already played 10 games for Washington this season. Jhonatan Solano, 27, was another option, but the club felt he hadn’t received enough at-bats in his rehab from a strained oblique suffered in July. He will go to instructional league in Viera, Fla. to stay warm in case the Nats need another catcher in September. Leon, 23, batted .250 in his 10 games with two doubles.

DeRosa, 37, is a known commodity – if he can stay healthy after another rough year with injuries. Johnson will use him as a depth infielder and an experienced pinch hitter.

Lannan, 27, we’ve discussed. He has a 3.99 career ERA and two Opening Day starts to his name. But he was cut at the very end of spring training in favor of Ross Detwiler and earned his $5 million big-league salary in the minors. He demanded a trade that never came and won two spot starts in Washington during the season.

Lannan must have been dreaming of this month all season because he’s coming off a pair of complete-game shutouts at Triple-A and 20 1/3 scoreless innings overall. Johnson said he will try to keep Lannan, Stephen Strasburg’s replacement, sharp by pitching him out of the bullpen a time or two. He could go as few as 14 days between starts f he gets the nod Sept. 12 against the Mets or as much as 20 days if he doesn’t pitch until Sept. 18 against the Dodgers. All depends on when they cash out on Strasburg and how the rotation is altered afterwards.

Perez is intriguing. Still just 22 and rail thin at 6-foot, 180 pounds, he is a fine defensive center fielder and had a .373 on-base percentage in 40 games with Syracuse. But he also stole 51 bases in 66 tries combined between Double-A Harrisburg and Triple-A. That’s a weapon Johnson says he needs off his bench.

“[Perez] is an impressive guy,” Rizzo said. “He’s a guy that really came on the radar screen two winters ago…when he was the rookie of the year in the Dominican Winter League. He hasn’t taken a step backwards. He’s moving forwards. He’s developing at a great pace. The player-development system has done a great job with him. He’s got some exciting skills and a right-handed bat we view as somebody that can really help us in the future.”

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