NEW YORK — Julius Randle apologized in a statement on his Instagram account on Friday, saying that his thumbs-down gesture to Knicks fans during Thursday’s win over the Boston Celtics as well as his postgame remarks were “an example of how sometimes you say things you regret to people you love.”

“Just want to send a quick message to our fans and be clear — I love NYC and being a part of this team and this franchise,” Randle wrote. “And like most Knicks fans, I am really passionate about us being successful.

“My family and I love how the fans and New Yorkers have embraced and accepted us and have made us feel great about our decision to commit long-term with the team this past summer. This support means the world to us.

“I understand that my actions also represent the league, this organization, and the city, and that I should have handled things last night differently and expressed myself with more professionalism and more appropriate language in the heat of the moment. My comment was an example of how sometimes you say things you regret to people you love, even if it came from a place of passion and deep love.

“Nobody wants to win more than me and I will continue to show loyalty and dedication to my teammates, the entire Knicks organization, and the fans who have shown me and my family so much love. I am going to keep focusing on the future.”

Randle gave fans at Madison Square Garden, who had been booing during the first part of the game, a thumbs-down after making a layup midway through the fourth quarter of New York’s come-from-behind win, and he appeared to shake his head after the crowd chanted “M-V-P” a minute later.

After the game, when asked what he meant by his thumbs-down to the fans, Randle bluntly said, “Shut the f— up.”

Randle was similarly blunt Wednesday after the Knicks practiced in Westchester, when asked what he thought about the negativity that has surrounded him this season.

“I really don’t give a f— what anybody has to say, to be honest,” Randle said. “I’m out there playing. Nobody knows the game out there better than I do, compared to what everybody has to say.

“So I really don’t give a s—. I just go out there and play.”

Randle’s thumbs-down gesture immediately stood out because of what happened with the New York Mets this summer, when shortstop Javier Baez hit a home run and gave the crowd at Citi Field a pair of thumbs down. Baez said later that his gesture was in response to the fans’ treatment of him and his teammates throughout the season.

Randle set career highs in several categories last season, including scoring, rebounding, assists, 3-point field goal percentage and free throw percentage, and signed a four-year, $117 million extension this offseason.

This season, though, has been far different. Randle’s production has dipped, most notably his 3-point shooting, which is down more than 8% from last season.

New York plays Boston again Saturday, this time on the road. The Knicks have won seven of their past 11 games — including 7 of 9 that Randle has played — and are in 10th place in the Eastern Conference.