The text message on baseball coach Ryan Kulik’s phone read like a mistake.

Hey, can you get a catcher for Hackenberg? He needs to throw a bullpen.

“I’m like, ‘Christian Hackenberg?’ ” Kulik recalled Saturday for The Post.

Indeed.

The former Jets quarterback — a second-round draft pick who flopped out of the NFL after three seasons and lost his starting job in the short-lived Alliance of American Football — is pursuing a professional baseball pitching career, as first reported by NBC Sports Philadelphia.

For the past month, Hackenberg has been training with Kulik, baseball coach at Division III Rutgers-Camden and a trainer at All-Pro Baseball Academy in Williamstown, N.J., who is working out of his backyard during quarantine.

“It’s not a joke,” Kulik said. “He’s all-in. He wants to do whatever it takes to reach his goal. And I think he can.”

Hackenberg, 25, was playing slow-pitch softball with a friend of Kulik’s when the idea to switch sports came up. He was a standout high school baseball player at Fork Union Military Academy in Virginia but gave up the sport as a five-star quarterback recruit for Penn State.

Baseball is a sport not kind to seven-year layoffs.

“He knows it’s going to take some time,” Kulik said. “But physically he’s got the body and the arm strength for it. He just has to work on his lower-half mechanics. It’s a little different throwing a football with your lower half than a baseball. The upper half is pretty similar, but you need more legs and drive to generate power in baseball. Once he figures that out, he is going to be pretty damn good.”