PHILADELPHIA -- The Phillies’ rotation is set through the first four games of the season. They should know everything by Thursday.

Phillies manager Joe Girardi said Wednesday that Zack Wheeler’s wife, Dominique, delivered a baby boy on Monday night. It is the Wheelers’ first child. Wheeler will be ready to make his Phillies debut on Saturday afternoon against the Marlins at Citizens Bank Park. He said earlier this month that he might have to miss a start or two following the birth of his child. It appears Wheeler will be in line to pitch the entire season.

• Nola gets Opening Day nod for Phillies

Aaron Nola will get the Opening Day start on Friday.

Vince Velasquez will pitch Sunday’s series finale against the Marlins.

Jake Arrieta will pitch Monday night against the Yankees. He pitched five innings in an intrasquad scrimmage on Wednesday at Citizens Bank Park, his final tune-up before the regular season. Arrieta struggled in the first inning, allowing three runs, but he did not allow a run the rest of the way. He threw 88 pitches.

“I felt good,” Arrieta said. “Pretty darn hot today. A really tough day. It’s good to kind of be worn out, get the pitch count up.”

The only uncertainty in the Phillies' rotation is Tuesday night’s starter against New York. Right-hander Zach Eflin is scheduled to throw four innings and at least 60 pitches in a simulated game on Thursday at Citizens Bank Park. If it goes well, he should start the fifth game of the season. If Eflin is not ready, the start could go to Nick Pivetta.