The Phllies opening day rotation is certainly not set in stone, and these Spring Training games might go a long way in determine who will fill the rotation.

But we no longer have to guess about the first three pitchers used in spring training.

New Phillies manager Joe Girardi announced on Tuesday that the first pitcher to get in a spring training game will be Nick Pivetta on Saturday against the Detroit Tigers in Lakewood.

The following day the Phillies will make their home debut where Aaron Nola will get the ball Sunday against the Pittsburgh Pirates in Clearwater..

After that, Vince Velasquez will start against the Baltimore Orioles in Clearwater.

"I think it's important that all these guys that are competing for the last spots get a ton of looks and we can afford to do that," Girardi told reporters on Tuesday in Clearwater.

Most people anticipate that the Phillies will open the season with Nola, newcomer Zach Wheeler, and Jake Arrieta in the top three slots in the rotation. If that's the case, the No. 4 and No. 5 spots in the rotation are up-for-grabs, making Pivetta, Velasquez and right-hander Zach Eflin's starts very important this spring.