WFAN’s war with ESPN Radio has hit a new level of “petty” thanks in part to Chris Carlin.

The recently fired WFAN host appeared as a “guest” on ESPN Radio’s “The Michael Kay Show,” the station and star Mike Francesa’s biggest ratings rival, on Wednesday afternoon, but didn’t use the platform to bash his former employer or colleagues.

“I don’t hold any ill will against anybody [at WFAN],” Carlin said.

However, WFAN did ensure Carlin was nothing more than a half-hour guest with co-host Peter Rosenberg off for Yom Kippur. Kay confirmed on the air that Entercom, WFAN’s parent company, told ESPN Radio right before the show started that Carlin could not be on for two hours because he would risk losing his remaining salary. Entercom did not immediately return a request for comment. Carlin’s contract runs out at the end of the year.

“They’re so mean-spirited and petty, to stop a guy from going on the air,” Kay said. “If he’s that bad that you fired him, what do you care if he’s on the air for two hours with us?”

Kay called the move “petty.” Carlin spent most of the segment talking Yankees and joking about his unemployment.

“Killing time, got out of the bathrobe for a couple of days,” he said. “You know, put on some pants.”

The former “Mike and the Mad Dog” producer was let go from his show “Carlin, Maggie & Bart” in September while his former co-hosts — Maggie Gray and Bart Scott — remained with the station and time slot. Carlin’s relationship with Francesa soured after Chris Russo left for SiriusXM in 2008 and Francesa believed Carlin sided with Russo.

Carlin also sent a profane text message to Francesa and Russo after they laughed about WFAN’s sinking ratings during Francesa’s brief retirement.

Carlin did speak about his reaction to his contract not being renewed, saying he was not surprised.

“Of course it’s gonna hurt,” he said. “I understand it. It’s a business decision, believe me.”

“Carlin, Maggie & Bart,” which has been renamed “Maggie Gray and Bart Scott,” had strong ratings but Entercom had been thinking about getting rid of the three salaries anyway, according to The Post’s Andrew Marchand

Carlin was then set up by Kay and co-host Don La Greca to take shots at Francesa and Russo when asked if he has lost his hair while producing Francesca and Russo. Carlin said he “wouldn’t say that” and blamed it on bad genes.

“It was an incredible experience for seven and a half years,” Carlin said. “Unbelievable.”

Carlin said he would not be rooting against his “best friends” Scott and Gray, whom he called “the breakout star” of the show. He did however joke that they could have hooked him up with a job outside of radio — saying he’d be happy to “park Bart’s car.”

“Maggie could’ve hired me to be the nanny,” Carlin said. “It wouldn’t have killed her.”