Sixteen years to the day after Paul Pierce, Kevin Garnett and Ray Allen etched their names in Boston sports lore, Jayson Tatum, Jaylen Brown and the rest of the 2023-24 Celtics did the same Monday night.

After being denied an NBA Finals sweep with a blowout road loss in Game 4, the Celtics bludgeoned the Dallas Mavericks 106-88 at TD Garden in Game 5 to clinch their first championship since 2008.

It was Boston’s 18th NBA title as a franchise, breaking a tie with the Los Angeles Lakers for the most in league history.

“You get very few chances in life to be great, and you get very few chances in life to carry on the ownership and responsibility of what these banners are,” said Joe Mazzulla, the NBA’s youngest championship-winning head coach since Bill Russell in 1969. “… And when you have few chances in life, you’ve just got to take the bull by the horns, and you’ve got to just own it. And our guys owned it.”

Tatum delivered a banner-worthy performance to lead the Celtics, finishing with 31 points, 11 assists, eight rebounds and two steals in 45 minutes. Co-star Brown added 21 points, eight boards, six assists and two steals in 44 minutes and was named NBA Finals MVP.

Both outplayed the Mavs’ top duo of Luka Doncic and Kyrie Irving.

“I share this with my brother and my partner in crime Jayson Tatum,” Brown, who also was the MVP of the Eastern Conference finals, said after receiving the award. “He was with me the whole way.”

Jrue Holiday, the lone prior champion on Boston’s roster, bounced back from his worst game of the postseason with a 15-point, 11-rebound double-double and was a game-best plus-21.

Derrick White went 4-for-8 on 3-pointers despite shattering a tooth in a first-half collision. Payton Pritchard touched the ball exactly once before garbage time yet hit one of the most important shots of the night: a miraculous halfcourt prayer as time expired in the first half.

Veteran tone-setter Al Horford capped one of the longest personal title droughts in NBA history, closing out Year 17 as a pro with his first championship in his 186th playoff game.

Holiday scored the Celtics first six points — all on shots at the rim — and added an early steal off an Irving drive. The teams combined to miss their first eight 3-point attempts before Horford buried one to put Boston up 9-2 and trigger a Mavericks timeout.

Dallas’ effectiveness from deep began to shift after Kristaps Porzingis entered to thunderous applause near the halfway point of the first quarter. Jason Kidd said the Mavs planned to put the banged-up big man’s movement ability to the test, and they did so instantly, generating open 3-point looks on three successive possessions.

Despite head coach Joe Mazzulla saying Porzingis would not have a minutes restriction after sitting out Games 3 and 4, the fan favorite was clearly limited. He played 16 minutes, finishing with five points and one rebound, and had his injured left ankle heavily wrapped for most of the game.

Boston maintained its lead, however, and stretched it to double digits with a 9-0 run to close out the first quarter. Sparking that flurry: Sam Hauser, who hit a three in front of an ecstatic Celtics bench and then intercepted a Doncic pass to initiate a Tatum-Brown fast break.

Brown couldn’t slam home Tatum’s alley-oop bid, but he finished with a layup, and Tatum added a driving bucket of his own after picking P.J. Washington’s pocket at the other end.

Hauser, the 3-point ace who endured long stretched of brutal inaccuracy this postseason, sank another three a minute into the second quarter. He also forced an Irving miss with a strong contest at the rim.

Tatum found success driving to the rack early in the second as Boston’s lead swelled to 15, but Dallas briefly yanked back momentum by exploiting a seldom-used Celtics lineup. They opted to go small with Tatum at center, and the Mavs went dunk, dunk, layup, layup on consecutive possessions before Mazzulla called timeout and reinserted Horford.

That substitution steadied Boston, setting the stage for an uproarious end to the first half. Tatum, Brown and Derrick White all drilled threes to help the Celtics reestablish control, with White’s coming minutes after he bashed his face on the Garden parquet while diving for a loose ball. ABC’s game broadcast later showed White grinning widely with a chipped front tooth.

But none of those matched Pritchard’s closing-time dagger from beyond halfcourt. Mazzulla inserted the diminutive guard with a flair for the dramatic after Doncic drew an and-one foul with four seconds left in the half. The Mavs star missed his free throw, Horford grabbed the rebound and Pritchard detonated a 43-footer as the horn sounded to put Boston up 67-46.

Those were the only four seconds Pritchard played in the game. He shot a woeful 3-for-16 from three in the series, but two of his makes were long-range buzzer-beaters. (Mazzulla called the other the “play of the game” in Boston’s Game 2 win.)

From there, the final 24 minutes were simply an exercise in maintenance for the Celtics. They never relented, and the type of Mavericks run that morphed Game 3 from a rout to a thriller never came. Boston led by at least 17 points for the entire second half.

Doncic finished with a respectable stat line (28 points, 12 assists, five rebounds) but turned the ball over five times and received little help from the rest of the Mavs’ roster. Irving, excellent during the two games in Dallas, again fell flat in his latest return to Causeway Street, where he has not won since 2021.

In three Finals games in Boston, Irving shot 34.0% from the floor and 17.6% from three.

The hoisting of the Larry O’Brien Trophy capped a dream season for the Celtics, who’d lost twice in the NBA Finals (2010 and ’22) and five times in the Eastern Conference finals since their most recent banner-raising. They were seven games better than any other club during the regular season, posted the third-best net rating in NBA history and then bulldozed their way through the playoffs, winning 16 of their 19 contests.

Since the NBA adopted its current playoff format in 2003, the 2016-17 Golden State Warriors (16-1) are the only other team to win a title with fewer than four postseason losses.

“It means the world,” Tatum said hands on head, before staring skyward in celebration.