BOSTON -- After missing two free throws with 7.6 seconds to go in overtime that would've given the Boston Celtics the lead, star guard Jaylen Brown took the blame for Boston's 120-117 overtime loss to the New York Knicks at TD Garden Thursday night.

"I've just got to be better, to be honest," Brown said after finishing with 22 points on 8-for-22 shooting and nine rebounds in 42 minutes. "Tonight was a rough game, and I'm a better basketball player than I played today.

"Those two missed free throws kind of embodied the whole game. I didn't get it going, didn't give my teammates enough energy to get the win, and that's what happens when you don't come out and give your best. I'll be better."

Boston (35-15), which has lost three straight after ripping off nine wins in a row before that, needed a furious fourth quarter comeback to even have a chance to win the game in the extra session. The Celtics trailed 102-89 with exactly eight minutes remaining after a pair of free throws by Knicks guard Miles McBride, but closed the game with a 21-8 run to tie things up.

The Celtics even had a chance to win the game in regulation. But a clean look at a jumper from Jayson Tatum -- who had 35 points, 14 rebounds and four assists on the day he was voted in as an All-Star starter for the first time in his career -- went wanting, sending the game into overtime.

"I felt like if I would have called a screen, they were going to double," Tatum said. "So I kind of just waved everybody down and made a move back to my spot, and it rattled in and out. But it felt good and thought it was a good one."

Boston then stretched that run all the way to 26-8 after Boston opened overtime with five straight points, and it appeared the Celtics were about to put New York (27-23) away. Instead, the Knicks fought back, scoring six straight points to retake the lead on an RJ Barrett 3-pointer with 29 seconds left -- one of only two baskets the Knicks hit in overtime.

After Brown made a layup on a baseline drive to put Boston back ahead by one, Julius Randle, who had a game-high 37 points to go along with nine rebounds, was fouled on a drive by Robert Williams and hit a pair of free throws to put New York back up by one.

Brown then went to the foul line after Jalen Brunson clipped his legs trying to contest a potential go-ahead jumper with 7.6 seconds left. Rather than put Boston back in front, Brown missed both and forced the Celtics to foul the Knicks on the ensuing possession.

Barrett knocked down a pair of free throws, and both Tatum and Malcolm Brogdon missed potential game-tying 3s.

"I think for your own sanity, just let it go," Brown said, when asked how he would process the missed foul shots. "Come out, keep playing basketball and come out and be a better version of yourself.

"I love this game, and I love the highs and the lows of it. It comes with it, so you don't shy away from it. You take it, you wear it and be better in the next one."

The Celtics still have the NBA's best record, though they now sit just one game up of the Philadelphia 76ers in the loss column.

And while Boston still ranks third overall in offensive rating and fifth in defensive rating, the Celtics rank 22nd in the league in offensive rating since early December -- a stretch of 24 games during which Boston has gone 14-10, the seventh-best record in the Eastern Conference over that span.

Over that stretch, the Celtics have dealt with a series of injuries -- including to Marcus Smart, who missed his third straight game with an ankle sprain, while Tatum and Brown are both dealing with nagging injuries. And there was little chance they were going to continue at the same pace as their scintillating start over the course of an entire 82-game season.

But, after another disappointing loss, Brown said it's on him to get Boston headed in the right direction.

"It's mentality," Brown said. "Having a tough mind. I think [Celtics interim coach Joe Mazzulla] talks about it all the time, having mental toughness.

"After losing two games tonight would be a great game to show that, and we dropped the ball, and I dropped the ball, as a leader. I didn't give the energy needed to help my team win and those two free throws just kind of embodied my whole performance tonight."