(Alex Brandon / AP)

Ryan Zimmerman’s first attempt at rehabbing his strained left hamstring fizzled because of inclement weather at Class A Potomac. The Nationals scratched Zimmerman shortly after the grounds crew at Pftizner Stadium removed the tarp in the midst of a steady drizzle. Potomac’s game still went on after an hour-long delay, but they did not want Zimmerman testing his hamstring in sloppy conditions.

The scratch will not necessarily cancel the Nationals’ plans to activate Zimmerman off the 15-day disabled list on Friday in Pittsburgh. General Manager Mike Rizzo said he would be comfortable with Zimmerman returning Friday, the first day he is eligible, after playing just one game in a minor league rehab assignment.

“I would leave it up to Zim,” Rizzo said.

Zimmerman had planned on playing three innings at third base and taking two at-bats tonight, then take three at-bats Wednesday night. He is still scheduled to play at Potomac on Wednesday. Rizzo said he would “re-think” Zimmerman’s schedule in the event of a rainout. Ultimately, the decision will be Zimmerman’s.