It remains remarkable — 16 years later — that a game of pickup basketball drastically altered the history of baseball’s most prominent franchise.

If Aaron Boone and his wife had plans that Friday night in Jan. 2004, the hero of the 2003 ALCS would have returned to the Yankees on a $5.75 million deal for the upcoming season with the ACL in his left knee still intact. If the third baseman had already done his cardio that day, Alex Rodriguez wouldn’t have joined the Yankees.

But Boone couldn’t have known a basketball game at a Newport Beach, Calif. gym would trigger the end of his playing career with the Yankees, keeping him out of pinstripes until returning as manager in 2018.

“I actually worked out with my trainer, but I didn’t do my cardio that day,” Boone said on Radio.com’s “Big Time Baseball” podcast with Jon Heyman and Tony Gwynn Jr. “And my brother-in-law was going to play a pickup basketball game that night and my wife and I had nothing going on.”

The career-altering play remains vivid in Boone’s mind.

“It wasn’t like I was rebounding or anything,” Boone said. “I was just going up and down the court.”

Boone was near the foul line, when a ball going out of bounds was thrown in his direction.

“The guy saved it … and I almost received a pass, like a football pass, over my shoulder, kind of going that way,” Boone said. “I went to go receive it and this guy came in and just wiped me out from the side. It was kind of violent and painful.”

Boone, who was violating the terms of his contract by playing basketball, instantly knew the severity of the injury.

“I got up and hopped off the court and cried as I drove home back to my house,” Boone said.

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Boone was released two weeks later and received 30 days termination pay, totaling $917,553. He missed the entire 2004 season, then spent the final five seasons of his playing career with four different teams. To replace Boone, Brian Cashman made one of the biggest trades in the sport’s history, acquiring the reigning AL MVP (Rodriguez), whose wild, successful, maligned and controversial tenure with the Yankees ended in 2016.

Meanwhile, the owner of one of the most famous home runs in baseball history — Boone’s Game 7 walk-off shot against the Red Sox — ended up playing a total of 71 games with the Yankees, including 17 in the postseason.

Boone doesn’t regret that game of basketball or telling the truth about the injury. If it doesn’t happen, maybe he isn’t leading one of baseball’s best teams now.

“I kind of believe everything happens for a reason,” Boone said. “It’s all part of your journey, part of your path. It was part of my path and it led me to other places and other teams and other great experiences that have all gone into shaping who I am. Life isn’t all good obviously and there are different adversities we all have to face, and you try and do the best with all of it. I’ve always had that attitude.”

“I don’t think I could ever say one thing or something you know led me to where I am now or led me to this job, but I think it’s all part of who I am,” Boone said. “All the things went into the pie that allowed me to be in this position. I think you don’t discount anything.”