Sonny Gray is starting a new chapter of his career in Cincinnati, searching for the All-Star form he held in Oakland.

And if it wasn’t for a season-and-a-half pit stop in New York, Gray isn’t so sure he’d be at a crossroads in his career.

Gray, who was acquired by the Yankees at the 2017 trade deadline as a potential ace — and ultimately was deemed unworthy to even make last year’s postseason roster after being demoted to the bullpen and posting a 4.90 ERA — believes the Yankees’ insistence on throwing a high percentage of sliders caused the right-hander to struggle, using a pitch he’s not confident in too often.

“They love sliders,” Gray told The Athletic. “Sliders are a great pitch. The numbers say slider is a good pitch, but you might not realize how many s–tty counts you’re getting in while throwing all those sliders. They wanted me to be [Masahiro] Tanaka and I’m way different from him.

“I can’t command my slider that well. I want to throw my slider in the dirt with two strikes, and that’s about it. I don’t have that type of slider, like Tanaka’s slider. His slider, the catcher will catch it, and the batter will swing and miss. If I get a swing and miss, the catcher is blocking it in the dirt. When I try to throw sliders for a strike, I get around it and it’s just a s–tty spinning pitch. I don’t know how people throw sliders for strikes that are still tight, good pitches. I’m at 2-0 and I’m throwing a slider, and either I’m throwing a s–tty slider in the zone, or I’m yanking it into the dirt and it’s 3-0 and I’m screwed either way.”

Yankees manager Aaron Boone did not entirely buy into Gray’s self-diagnosis.

“I hadn’t heard that,” Boone said in Tampa. “Nothing really. We tried the best we could to try and get him to be successful. We all kind of shared in the frustration at times. I know he was frustrated, but we just tried to get him to be the best he could be. I don’t know if I would characterize it as we pushed him. He throws a slider, so …’’

According to Brooks Baseball, Gray threw 11.2 percent sliders in 2016, his last full season with Oakland, before throwing 15.3 percent in 2017 (split between the A’s and Yankees) and 15.9 percent in 2018, all with the Yanks. Fangraphs shows Gray’s slider percentages as 12.0, 16.1 and 17.0 between 2016 and 2018. However, both web sites show show Gray’s slider numbers in the 16 percent range in 2015 with Oakland (16.7, 15.9).

Gray, who was traded to the Reds in January, believes throwing so many sliders also negatively affected the quality of his curveball.

“I didn’t throw as many curveballs, and that’s when it started to morph and lose shape,” Gray said.

After being bounced from the rotation last year, Gray said he ditched the breaking balls in a scoreless, two-inning relief appearance — with three strikeouts, one hit and no walks — against the Red Sox on Sept. 29.

“In my very last outing against the Red Sox, second-to-last game of the season in New York, I threw two innings out of the pen, all I did was throw cutters,” Gray said. “I said, ‘F–k ’em, all I’m going to do is throw cutters today.’ I just threw 94-mph cutters. … [Pitched well, and] I thought maybe I’ll make the postseason roster here … but I didn’t.”

Even if the 29-year-old could be trusted on the road, where he posted a 3.17 ERA, the Yankees couldn’t pitch him in the Bronx, where he held a 6.98 ERA last season, and walked nearly twice as many hitters (5.3) than away from New York.

“That’s the question,” Gray said of the walks. “It was insane. It wasn’t like two or three starts, either, pretty large sample, with that drastic of a split.”

Gray said he asked the coaching staff what it thought.

“Am I nuts? Do you see a difference? What’s the difference?” Gray said. “They said, ‘No, you’ve just been unlucky.’ I was like, ‘That’s bulls–t.’”

Additional reporting by George A. King III