Bryce Harper, shown taking batting practice in D.C. on Sunday, hit off live pitching Tuesday in Atlanta. (Mark Tenally/Associated Press)

ATLANTA — A man in a strange uniform — a dark green camouflage shirt, gray baseball pants and a navy hat with a red brim — hit on the field Tuesday afternoon at SunTrust Park, hours before his team’s game against the Atlanta Braves. He took decidedly normal-looking swings, and even homered. He shook hands with two young pitchers flown in just to pitch to him, handpicked to do so because they could command the strike zone and wouldn’t threaten him with wildness. He ran the bases — lightly, but ran them. He fielded ground balls and jogged off the field with what seemed to be a spring in his step. He hasn’t run off the field in more than a month.

But Bryce Harper is getting closer to running on and off the field with his teammates around him. Because minor league seasons are over, Harper cannot go on a traditional rehab assignment to work his way back into game shape after his mid-August knee injury. The Nationals are bringing simulated games to him.

They flew two young pitchers — right-handers Sterling Sharp and Brigham Hill — to Atlanta to pitch to him in a simulated game Tuesday afternoon. Presumably, he will need more live at-bats before returning to game action. He has not played in a game since Aug. 12.

“It went well. He moved well. He ran pretty good,” Nationals Manager Dusty Baker said. “His timing was off a little, but not too bad … we’ll just have to see how he feels tomorrow. Tomorrow’s the key.”

Nationals General Manager Mike Rizzo stood right behind the batting cage watching Harper throughout the workout, towel over his head to block the sweltering September sun in which Harper made his most promising progress yet. Rizzo said the Nationals will make their next decisions about Harper’s future Wednesday. As always with rehab workouts, a player’s health the day after generally determines more than the workout itself.

If all goes well, Harper will have another workout after the day off — Dusty Baker suggested another simulated game in New York, while Rizzo was more vague. But for now, it seems Harper will remain with the Nationals as he works his way back to being major league ready. The Nationals did begin instructional league play in West Palm Beach, Fla., this week and could decide to send him there if needed.

“We’ll see how he feels and see how many at-bats he wants to get,” Rizzo said. “We’re going to kind of take it day by day and see what his thoughts are.”

Stephen Drew also hit in the game with Harper, then jogged around the outfield as part of his ongoing effort to return from the tear of his abdominal muscle away from the bone. Drew has not yet given up on returning this season, though he has just two weeks to do so and is not yet able to sprint. Brian Goodwin ran in the outfield a half-hour after Harper’s game, doing sprints under strict supervision. Goodwin has been out since Aug. 13 due to a groin injury, and his progress has been slow — so slow that the Nationals decided to call up Victor Robles to provide outfield depth in case Goodwin (or maybe Harper) cannot return. Rizzo seemed to think Goodwin will run out of time to get ready before October.

“He’s pretty far behind Harp’s rehab schedule,” Rizzo said. “We’re going to have to see where he’s at and see if we can accelerate the process a little bit.”

Harper’s progress, obviously, is more promising, with two and a half weeks before Game 1 of the National League Division Series. Harper put on a powerful batting practice display before Sunday night’s win over the Dodgers. Since he cannot get innings with a minor league team, the Nationals could decide to ease him back into action in the big leagues.

The concern about throwing Harper, or any injured player, right back into major league action always centers on the speed of the game. Since those games matter, and are played at the highest level, rehabbers often cannot hold back like they might in the minors — 0 to 60, in too few seconds. But for the Nationals, these games hardly matter at all. Perhaps the Nationals can nurse Harper back into big league games more quickly than normal without risking any trouble. Perhaps he will want more at-bats than big league life can give him between now and October.

“It’s conceivable [that he could be back before the end of the regular season],” Rizzo said. “But we’re going to take it day by day. He’s itching to come back and play. The leg feels good, so that’s positive … if strong enough to play some games and get a lot of at-bats in instructional league, then maybe it’s possible he could come back some time before the season ends.”

Whatever his exact timeline, Harper seems likely to return by October, like the Nationals expected he would all along. When he does, the Nationals will have their full team — complete with corrected bullpen and intact outfield (minus Adam Eaton) — for the first time all season.

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