After making it through last night's game at Class A Potomac with no problems, Ryan Zimmerman is set to come off the disabled list and rejoin the Nationals lineup tomorrow night in Pittsburgh.

Zimmerman, out since April 18 with a strained left hamstring, went 0-for-3 and reached on an error while on rehab at Potomac, playing six innings in the field without reporting any problems.

It was Zimmerman's only appearance on the rehab assignment — he was scratched from the lineup Tuesday night due to wet grounds at Pfitzner Stadium — but the Nationals aren't concerned he needs more at-bats before returning to the big leagues.

"I'm not concerned about him even playing," manager Davey Johnson said. "I think last year he did a stint on the DL, and he didn't rehab anywhere. I feel the same way this year."