Zimmermann will start tomorrow, Williams remains undecided on Sunday

BALTIMORE - Nationals manager Matt Williams said right-hander Jordan Zimmermann will return from paternity leave to start tomorrow night's game against the Orioles. Zimmermann's wife, Mandy, gave birth to their daughter, Ava Kristeen, this morning.

"Now that we know that everybody's healthy and everybody's gonna be home, Jordan is gonna pitch tomorrow and determine Sunday at some point tomorrow," Williams said.

Right-hander Max Scherzer threw his bullpen session this afternoon at Camden Yards, leaving a hint he is preparing to take the mound on Sunday. It's likely that Scherzer will start the series finale but Williams only went so far to say that his ace is an option. If Scherzer does pitch Sunday, he wouldn't be available to appear in Tuesday's All-Star Game.

Wednesday's postponement leaves Gio Gonzalez entering tonight's start on a full week's rest. Last Friday, the left-hander held the Giants to one run on five hits over seven innings in the Nats' 2-1 win. It was the second straight superb outing from Gonzalez, who's allowed two runs or fewer in four of his past five starts.

"He was so excited to go the other night," Williams said. "He's been pitching well. When you get the rainout like that with an off-day following, it's a little wrench thrown into the mix. He was immediately in the office after (wanting to know) what was gonna happen today. So we told him he'd go ahead and start today. So he's excited about it and he's itching to go again."

Including his time in Oakland and D.C., Gonzalez is 1-4 with a 3.80 ERA in seven career starts against the Orioles.

"He's pitched against these guys," Williams said. "He understands them. So hopefully tonight it's more of the same where he can land the curveball early and throw the fastball for strikes when he wants to (and) elevate when he needs to and hold this team down. It's a powerful team we've seen way too many times already."

The Nationals reinstated right-hander Aaron Barrett (right bicep strain) from the 15-day disabled list this afternoon when Zimmermann shifted to paternity leave. Barrett, whose last appearance with Washington was June 11, is 3-2 with a 5.06 ERA in 21 1/3 innings this season.

"He's our strikeout guy against a tough right-handed hitter in a pressure situation," Williams said. "And he's ready for that like he always is. So if that opportunity presents itself tonight, then he's an option for us."

The Nationals welcomed bench coach Randy Knorr back for this weekend's series. Knorr has been away from the team since his wife passed away on June 24.

"We as a coaching staff told him 'whenever you're ready,'" Williams said. "So he called back this week and said 'I'd like to be in there on Friday and get back at it. I need to get back to the dugout. It's a comfort for me.' So we're glad to have him back. We're whole as a coaching staff again now."