WOODBRIDGE, Va. -- Nationals third baseman Ryan Zimmerman declared himself ready to join the club after playing six innings in a rehab game at Class A Potomac on Wednesday night.

Zimmerman, on the disabled list since April 21 with a strained left hamstring, played third base and took three at-bats for Potomac. He plans to work out at Nationals Park on Thursday before flying to Pittsburgh that night, ahead of the Nationals' series against the Pirates, which begins on Friday.

"Everything felt good. Arm feels great. Hammy feels great," Zimmerman said. "So now it's just time to get back out there and get going."

Zimmerman went 0-for-3 and said he was glad to see a mixture of pitches. He grounded out to shortstop, flied out to center field and reached base on a fielding error by Carolina third baseman Yhoxian Medina, all with no ill effects from the hamstring injury that has kept him out of the Nationals' lineup since April 17.

"It only took seven, eight days for it to get completely better," Zimmerman said. "But then obviously you have to get back in game shape and play a couple games and get ready, so thankfully everything kind of went as planned and nothing really came back up. It's good. Hammies, you never really know."

Zimmerman, who has had a problem with throwing errors this season, started a force play at second base in the second inning on the only ground ball hit to him. He also charged toward home to catch a popped-up bunt.

"Unfortunately I made some errors, but my arm feels great now," Zimmerman said. "Everything feels good, and all you've got to do is keep going out there and try to make plays."

Before his injury, Zimmerman was hitting .226 with one home run and 11 RBIs in 15 games. The Nationals have been through their struggles as well, but Zimmerman isn't concerned.

"It's early. It's May 1," he said. "Everyone is a lot more worried than we are. Do we want to go 15-5 or 20-10 every month? Of course, but that's not going to happen. We've just got to come back out and keep playing and keep getting better every night. Jordan [Zimmermann] threw great tonight. We've got a long ways to go, 160-something games to go. I like our chances."