Retired NHL star Claude Lemieux died of a broken heart, according to people who knew him.

During his two-decade career, he led the Montreal Canadiens, New Jersey Devils and Colorado Avalanche to a total of four Stanley Cups and was the ninth best playoff scorer of all time — but he was never inducted into the Hockey Hall of Fame after he hung up his skates in 2009.

Lemieux, a “tough guy” on the ice who was known to be deeply sensitive to rejection, never got over being passed over for the top honor, according to his pals.

“He always lived this as an injustice, a heavy burden to bear,” Rejean Tremblay, a longtime Montreal hockey columnist and insider who knew Lemieux for 30 years, told The Post.

“The sense of rejection ran deeper than one might have imagined. He took it very hard.”

Lemieux could be traumatized by rejection, like the time he was sent down to the minor leagues in 1985 after his first NHL season. He was so devastated, he once told Tremblay,  that he smashed his car’s windshield and drove with it broken the 100 miles from Montreal to Sherbrooke, where he refused to stay in the apartment the team rented for him. 

The hockey legend hanged himself in the warehouse of his family’s furniture business in Palm Beach County, FL. His body was found shortly after 3:30 a.m. Thursday.

The iconic hockey team where he broke in as an 18-year-old rookie from Gatineau, Quebec, brought him back this past Monday to carry the torch at the Bell Centre – a team tradition – before Game 3 of the NHL conference finals against the Carolina Hurricanes. He was all smiles, as an adoring crowd of 21,000 people cheered him on.

“It’s possible that surge of love, that wave of love on Monday evening, triggered an emotion that was too intense,” Tremblay said, citing NHL friends close to Lemieux.

“It might have reawakened old pains, old suffering.”

Lemieux, who died at 60, also went some 10 years without speaking to his children, according to sources — another emotional load that weighed heavy on his heart in the years after his retirement.

“It hurt him tremendously,” said Tremblay.

He had been depressed leading up to his suicide, according to his family, but they had no idea he was planning to take his own life.

“They didn’t expect that at all, they never saw it coming” Colombe Lacroix, a close family friend who was at the scene with the family Thursday, told The Post. “He’s been going through a difficult time, he was depressed.”

“It’s so devastating, everyone is upside down,” she said in tears. “Brendan is completely destroyed,” she said of Lemieux’s 30-year-old hockey player son who found his dad’s body.

She said Claude Lemieux saw his own parents for the last time when he was in Montreal this week, and also made a point of bringing his two oldest sons from his first marriage, Michael and Christopher, on the trip.

Lacroix, the widow of former Colorado Avalanche general manager and hockey legend Pierre Lacroix, became close with Lemieux and his wife Deborah when Lemieux played for the team between 1995 and 1999. The two couples lived in the same Denver area neighborhood of Columbine, made infamous by the 1999 high school massacre.

She had just moved to Florida, and lived 40 minutes away from the Lemieuxs.

“I held Claude in my arms, and I said thank you for being there for me,” she recounted of the last time she saw her good friend.

“He left our world too soon and I hope he’s in a better place and that he’s happy.”