LOS ANGELES -- This is it. It is finally going to happen.

Nick Pivetta is scheduled to make his big league debut Sunday afternoon against the Dodgers at Dodger Stadium. He joined the Phillies in July 2015, when they traded disgruntled closer Jonathan Papelbon to the Nationals.

Pivetta made 37 starts with Double-A Reading and Triple-A Lehigh Valley since then before getting called to Philiadelphia last week to take Aaron Nola 's place in the rotation last Wednesday against the Marlins at Citizens Bank Park.

But Tuesday's game got postponed because of rain, pushing back Pivetta's start to Sunday.

"It's so surreal being here," Pivetta said Saturday. "It's met my expectations and more."

Pivetta, who is the organization's No. 12 prospect, according to MLBPipeline.com, said he will have 15 family and friends from British Columbia, Canada, in attendance Sunday. Many of them had booked flights to Philadelphia to attend Wednesday's game. Fortunately, Pivetta caught most of them before they boarded their flights.

"Pretty much everyone was in the airport at that time," he said. "It was a bit of a hectic situation. Had to call everyone and say, 'Cancel your trip because I'm not pitching anymore.'"

But Sunday, he will pitch. Pivetta is expected to be officially added to the 25-man roster Sunday morning. A corresponding move will be made then.

"They've gone by really, really slow," he said about the past few days. "I'm happy that I'm throwing a day game tomorrow because I'll be able to wake up and I'll be on the mound. There's not a lot of sitting around and waiting.

"Right now, it's nice. I'm calm and easy. But I'm sure when I get out there it will be a lot different. There's going to be a lot more emotions. I'm going to try and settle down as much as I can because I don't want the game to get away from me. I want to be like I've been here before."

Pivetta earned this shot because he went 3-0 with a 0.95 ERA in three starts with the IronPigs. He struck out 24 and walked two in 19 innings. He credited his ability to throw his fastball for strikes as a key to his success.

And now he gets to throw it against big leaguers.

"It's something that I've worked my whole, entire life to do," he said. "I've put a lot of other things aside for this."

Todd Zolecki has covered the Phillies since 2003, and for MLB.com since 2009. Follow him on Twitter and Facebook and listen to his podcast.