Basketball, Dick Barnett said, was always his “mistress” growing up — his word. Wooed him to the playground the night of his senior prom. Served as his steady during a college career that featured more gym time than classroom time. The first time around, anyway.

It took a while, but Barnett, best known for being part of New York Knicks championship teams in 1970 and ’73, would eventually learn how fickle that mistress could be. Then he would begin learning, period.

The 82-year-old Barnett — now Dr. Richard Barnett, thank you very much — has told the story of his educational epiphany more than once, and he told it again last Thursday, the day before the 1957-59 editions of his college team, Tennessee A&I (now Tennessee State), was inducted into the Basketball Hall of Fame. That team, coached by a man already in the HOF, John McLendon, won three consecutive NAIA championships, and Barnett was an All-American each of those seasons.

He would go on to a 15-year professional career, spending 14 in the NBA and one with George Steinbrenner’s Cleveland Pipers, who played in something called the ABL. Barnett is remembered for punctuating his unorthodox jumper with a signature bit of trash talk — “Fall back, baby” — though it’s not exactly clear how that started. The Knicks retired his No. 12 in 1990, and have in fact retired the numbers of the entire starting five from that first title team. His high school and college exploits have also landed him in three Halls of Fame.

Yet he speaks just as readily about his three degrees, the 23 books he has written and the lectures he has delivered all over the world. And the genesis of that, he told the crowd gathered in the Hall of Fame for the inductees’ jacket presentation, came on Feb. 18, 1967, when he tore an Achilles in a Knicks game against the Cincinnati Royals.

“The chickens came home to roost,” he said.

He can still remember the trainer telling him his career might be over. He can still remember thinking that if that were the case he had nothing to fall back on; credit-wise, he was still only a college sophomore. But he earned his bachelors degree in physical education from Cal Poly the following year (even while learning his basketball career wasn’t close to being over; he played seven more years after ‘66-67). In 1974 — the same year he retired from the NBA — he earned a masters in public administration from NYU, and in ‘91 added a doctorate in education from Fordham.

He has since spent four years as a professor at St. John’s, teaching sports management, though his focus has been more far-reaching. He once ran the Athletics Role Models Educational Institute, and now operates the Dr. Richard Barnett Center for Sports Education, Business and Technology.

All with the idea of helping young people focus on what matters most. (And others as well; his taped speech the night of the Hall induction centered on the struggle for civil rights in the 1950s.)

As mentioned, his focus was far narrower in his younger years. In last Thursday’s address he said some 350 students from Roosevelt High School in Gary, Ind., attended the prom.

“I was the only one that did not go,” he said.

He was out on the court when everybody arrived for the prom at 5 p.m., he said, and still there when everybody left, five hours later.

“Me and my basketball,” he said. “Me and my dream. … We had a rendezvous with destiny.”

Little did he know that his destiny would someday change. And that that would make all the difference.