(Jim Prisching/AP)

Following his last start last Saturday, Johnson revealed that Zimmermann had trouble getting his shoulder loose while playing catch. Zimmermann has been orally taking medication to help the inflammation since Monday. Johnson stressed that it wasn’t a major concern because the right-hander’s performance hasn’t dropped but he hoped giving him an extra day would help. Zimmermann will now get six days of rest in between starts.

“It’s not a big deal because he’s feeling good, a lot better than he has been,” Johnson said. “He’s been pitching lights out, so that’s good.”

Zimmermann has had as dominant a past month as any pitcher in baseball, posting a 4-0 record and a major league-leading 0.97 ERA in six starts in July. He also led the National League in walks and hits allowed per inning (0.84 WHIP) and was tied for the lead in wins for the month. On a starting rotation with two all-stars, Zimmermann owns the Nationals’ lowest ERA (2.28).

Last Saturday, Zimmermann allowed only one run and Johnson pulled him after six innings after only 93 pitches, cautious of his shoulder. Zimmermann has pitched at least six innings in his past 21 starts — now the longest streak in baseball after Justin Verlander’s streak was snapped in a rain-shortened game on Tuesday.

Zimmerman is also on pace to pitch the most he has in his career this season. He pitched only 161 1/3 innings last season, his first after recovering from Tommy John surgery, and has already thrown 134 1/3 innings this season.

Zimmermann hit as high as 97 mph on the radar gun in Milwaukee, Johnson said, and thus it isn’t cause for alarm. Zimmermann started the Nationals first game back from the all-star break on July 13 so Johnson said he didn’t mind giving the right-hander an extra day this week.

“It’s not a big concern,” Johnson said.

Because of Monday’s offday, both Gonzalez and Zimmermann were already afforded an extra day before their starts. Even by moving Gonzalez up a day, he still gets a full four days of rest in between starts and can throw his bullpen session in between starts on Wednesday.

Gonzalez will start the night game of Friday’s doubleheader against the Miami Marlins and John Lannan will be called up from Class AAA Syracuse to start the day’s first game.

The Nationals have been lucky to avoid injuries to their starters this season, the backbone of their success. Aside from Lannan’s previous callup start, they have used only seven starters this season.

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