Those looking for tales of fast women, drugs and debauchery inside the 1986 Mets’ clubhouse won’t find it in “I’m Keith Hernandez.”

Yes, the title is plucked from the iconic “Seinfeld” scene in which the cocksure former big leaguer, playing himself, attempts to work up the gumption to kiss Elaine Benes. In an inner monologue, he reminds himself that he’s the Keith Hernandez: the five-time All-Star who won two World Series titles and 11 Gold Glove awards and was the 1979 co-MVP of the National League.

However, in his upcoming memoir (Little, Brown and Company), we meet a very different version of the former Met — the pre-mustache, pre-persona Hernandez.

Drafted by the St. Louis Cardinals in 1971, Hernandez was a sheltered Northern California kid who was riddled with self doubt as he tried to find his stride on and off the diamond. The young first baseman was just discovering booze and marijuana, and was still too shy to talk to girls.

He was sharing cramped hotel rooms with teammates, and hadn’t yet discovered late nights at Elaine’s. Instead, he was filling his teenage belly at a $6 all-you-can-eat joint in St. Petersburg, Fla., during spring training.

This trip down memory lane ends in 1980 — three years before he even arrives in New York.

“That’s the evolution of my life right there,” Hernandez, now 64, tells The Post.

“I came into my own after the MVP year” in 1979, he says. But “people in New York saw the finished product. They don’t know about my trials and tribulations.

“I think it’s important that people see my vulnerability and fragility when I was young,” he adds.

As an up-and-comer, Hernandez weathered batting slumps, benchings and demotions — including in 1975, when the Cardinals sent him packing back to Triple-A ball in Tulsa, Okla. He dealt with many of these disappointments in a most vulnerable way: He cried. In baseball.

“My mom used to always tell me, ‘It’s OK for men to cry.’ It clears your mind and gets rid of the emotion and you don’t wallow in it. You get over it and dig in deeper and fight back harder. I’m not at all ashamed or abashed of how I cried,” says Hernandez.

And even when he was playing well — like when he made it to the majors in late 1974 — he fumbled socially. Hernandez recalls trying to join his Cardinals teammates at a Philadelphia hotel bar when veteran outfielder Reggie Smith told him to “go someplace else, rook.”

“So I left the bar with my tail between my legs and tried not to take it personally. What was I thinking, anyway?” he writes.

But it’s not a total pity party. The tome is filled with triumphant milestones like his first major league home run (against the Dodgers in 1975) and his winning co-MVP in 1979.

And there are the dirty exploits and details of life on the road. The day he was called up from AA to play for the AAA Tulsa Oilers, a squirming Hernandez told his new manager, “I’m sorry, but I think I got the clap.” (His new skipper calmly responded, “OK, I’ll get the team doctor over here, but you’re playing tonight.”)

In Tulsa, he attended “more than a handful” of local cockfights, where he first saw a woman shoot up crystal meth. The eye-opening experience only intensified his determination to climb to the highest rungs of the sport.

“That stuff wasn’t for me. More than ever, I wanted to be a Major League Baseball player,” he writes.

Woven into the book are tales from his current life as a cat-owning bachelor in the Hamptons and a Mets broadcaster for SNY— a gig he partially credits to legendary restaurant owner Elaine Kaufman. After he retired in 1991, he had stepped away from the game and was rudderless.

“She is the one who threw a bucket of cold water on my face and told me to get off my ass and do something,” says Hernandez. It was at the Upper East Side institution where he met his future agent.

Though it’s a serious baseball memoir, it’s equally an exploration of his complex relationship with his father, John Hernandez. His dad — a former minor league player — fostered his love for the game. He built his sons (Keith’s older brother, Gary, also played in the minors) crude batting cages, regaled them with tales of his own playing days and drilled the game’s fundamentals into them.

But he was also difficult and unrelenting: Even as Hernandez was playing in the country’s most prominent ballparks, his father still pushed unsolicited batting advice — and criticism.

Hernandez’s simmering resentment of his father surfaced in a 1986 Sports Illustrated story. “I was angry at him and I revealed some things in that story that I should not have. He wasn’t happy about it,” says Hernandez.

Today, he’s less harsh. “I grew up in a loving family. My dad was tough. He instilled in us a work ethic and integrity.”

His father died a year after he retired. “It was almost like he was put on this Earth to make me a big league ballplayer,” Hernandez says. “We never really had . . . a father-son talk, to get it [all out] on the table and go forward. I really regret that we didn’t have that chance.”

In the book, he attempts to plug that hole with a poignant anecdote from his young adulthood. In 1980, when Hernandez returned home for the first time after winning the NL MVP, his father pulled out the family’s projector.

To his surprise, his dad’s choice of entertainment was footage of him playing baseball as an 11-year-old.

As Hernandez watched his younger self at the plate, his father said, “When you were 11 years old, I knew you had something special.”

“I was stunned,” Hernandez writes. “Seeing Dad behind the projector, so proud of what he was showing on the screen, I realized why he’d been so hard on me as a kid.”