When he gets going, it’s almost unstoppable to stop Jayson Tatum.

The Knicks learned that again on Monday night at TD Garden.

Tatum scored 35 points, including 23 in the second half and 17 in the fourth quarter, as the Celtics superstar continued his MVP-caliber start to the season. He was the difference as the Celtics, in a dog fight with the Knicks for most of the night, pulled away for a 114-98 victory.

Jaylen Brown added 22 points and Kristaps Porzingis had 21 for the Celtics, who won their third game in a row. The C’s, like in the season opener at Madison Square Garden, struggled to find separation against Jalen Brunson and the tough Knicks, but they relied on one of their better defensive efforts of the season to turn the game around.

The Celtics and Knicks traded haymakers for most of the first three quarters, neither budging before the C’s finally got some breathing room. The game was tied at 72 with 3:05 to go before the Celtics went on a 12-4 run to close the quarter, which included Jrue Holiday’s 3-pointer with nine seconds left in the period to give the Celtics an eight-point lead.

The Celtics struggled to contain the Knicks to one shot, but they turned up the pressure defensively in the second half. Then Tatum took over. He completed a four-point play to put the Celtics up eight, and he hit back-to-back 3-pointers with 3:30 to play to put the game away.

Takeaways:

– The Celtics were a step behind the Knicks for a majority of the first half before they finally kicked it into gear over the final 75 seconds of the second quarter to give them some momentum. The C’s went on a 9-2 run to end the half, which began with a Porzingis hook shot before Derrick White blocked a shot from Jalen Brunson that led to a transition dunk for Tatum. Another stop then led to a breakaway layup for Payton Pritchard. After Brunson hit a tough shot with eight seconds to go, Brown made a 3-pointer at the buzzer to cut Boston’s deficit to one at halftime.

– Sam Hauser’s hot November continued as he went 4-for-6 from 3-point range, which included a big triple in their run to end the third quarter. He’s now shooting 25-for-44 (56.8 percent) from deep this month.

Hauser has continued to make an impact beyond hit shooting, too. He also pulled down five rebounds in 21 minutes, and held his own defensively – which has been an early theme this season as he’s become a reliable option off the bench.

– Tatum’s post-up game continued to make a big impact for him. Three of his first six makes of the game were from the post, which included one play where he bullied Josh Hart and imposed his physicality on him to get an easy bucket.

– In their first meeting of the season in the season opener, the Knicks dominated the offensive glass with 17 offensive boards that led to 20 second-chance points. That theme continued Monday as the visitors scored 10 early second-chance points to build a lead in the second quarter. But the C’s ultimately cleaned it up, allowing just 12 offensive boards for 14 second-chance points in the game.