LOS ANGELES (AFP) — Jayson Tatum said the bitter sting of past postseason defeats powered the Boston Celtics to their record-breaking 18th National Basketball Association (NBA) championship title on Monday against the Dallas Mavericks.

The 26-year-old Celtics star produced a masterful 31-point performance as Boston completed a 4-1 series triumph with a resounding 106-88 victory.

The win couldn’t have been sweeter for Tatum, who just over a year ago was being derided as a playoff “choker” after the Celtics suffered a traumatic game seven home court defeat to Miami in the Eastern Conference finals.

That shattering loss came a year after the Celtics had lost 4-2 to Golden State in the NBA Finals, with the Warriors clinching the series on Boston’s home court.

Tatum said those back-to-back defeats had left Boston with a “relentless” desire to finally close out a championship.

“It took being on the other side of this and losing in the Finals and being at literally the lowest point in a basketball career that you could be, to next year, to the following year, thinking that was going to be the time, and come up short again,” Tatum said.

“Coming up short and having failures makes this moment that much better. Because you know what it feels like to lose.”

“You know what it feels like to be on the other side of this and be in the locker room and hearing the other team celebrating, hearing them celebrate on your home floor.”

“That was devastating.”

Tatum was all smiles on Monday after finally entering the NBA’s winner’s circle.

“It’s a hell of a feeling,” Tatum said.

“I dreamed about what it would be like, but this is 10 times better.”

Celtics coach Joe Mazzulla, who at 35 is the youngest head coach to win an NBA crown since Bill Russell in 1968 at the age of 34, said past disappointments had forged a determination to succeed amongst his players.

“It really starts with them,” Mazzulla said.

“You can’t have a philosophy or a way of playing if you don’t have a group of guys that are willing to buy into it and be disciplined.”

“Quite honestly, this group of guys has been through so much in the league, they know what it takes.”

The Celtics win was also a personal triumph for Mazzulla, who was thrust into the head coaching role in the 2022-2023 season after the abrupt departure of predecessor Ime Udoka due to a sex scandal.