Mets starting pitcher Jacob deGrom looks on during a game...

Mets starting pitcher Jacob deGrom looks on during a game against the Rockies at Citi Field on Sunday. Credit: Brad Penner

PHILADELPHIA — Jacob deGrom is going to start Sunday, and the Mets mean it this time.

After scratching the righthander from his previous start on short notice because of a hyperextended right elbow — they were just being cautious, they said — the Mets will have deGrom on the mound Sunday against the Phillies. They chose to stick with that plan even after Saturday’s rainout, moving Noah Syndergaard to Tuesday at home against the Blue Jays.

DeGrom won’t have special pitch-count limitations, but manager Mickey Callaway said the team is still discussing protocol for his plate appearances. He previously said deGrom won’t be allowed to swing as long as he feels discomfort in his right elbow when doing so.

DeGrom hasn’t pitched since May 2, when he dominated the Braves for four innings but left the game after hurting his elbow on a whiff, a sensation he has felt before.

DeGrom avoided a major issue, but the scare spurred change. The Mets are asking their starting pitchers to wear an additional protective brace on their throwing elbow while batting.

“That keeps their arms from locking out, especially those guys that hit opposite-handed,” Callaway said. “It won’t let it hyperextend.”

DeGrom, Syndergaard and Zack Wheeler throw righty but bat lefty. Steven Matz throws lefty but bats righty. That means all four pitchers have their throwing arm exposed to pitches when standing at the plate, and that front arm is more at risk for hyperextension on a hard swing.

Of the Mets’ starters, only lefthander Jason Vargas (skipped this time through the rotation) bats and throws from the same side.

“We’re going to try to get them all to wear it,” Callaway said. “They would wear anything to protect them a little bit.”

Mickey pulling for Harvey

As Matt Harvey tossed one-hit ball over four scoreless innings Friday for the Reds — his first game for any club other than the Mets — Callaway watched on TV from Philadelphia.

“That was really good,” Callaway said. “I sent him a text and said, ‘Way to go.’ I’m pulling for him.”

Meet the Mets babies

The Mets had as many run-producing swings as they did babies Friday: two.

Jay Bruce and his wife, Hannah, had a son, Maxwell. David Wright and his wife, Molly, had a daughter, Madison. It was the second child for each couple.

Reliever Jerry Blevins is scheduled to become a father in the next few days.