The Boston Celtics and Oklahoma City Thunder played out a thrilling contest on Tuesday night that came right down to the wire.The C's came out on top in the closing stages as they fought back from a late deficit to claim a 100-99 win at TD Garden.Boston's victory simply didn't seem possible as they trailed by six points with just 12.7 seconds remaining.But they took full advantage of OKC's failure to close the game out with some late free throws and as they've done on numerous occasions this season, they were able to claim an improbable victory from the jaws of defeat.The hero of the night was Marcus Morris, who nailed the game-winning three-pointer to send the crowd into raptures.With the Celtics trailing 99-97 with 7.7 seconds on the clock, they could easily have taken the safe option and gone for a two to tie the game and take it into overtime.After the ball was inbounded and swung over to Jayson Tatum, the rookie immediately dribbled into the paint but chose to kick the ball out to Morris.The power forward was quickly closed out by Paul George but he smartly hit him with a pump fake to create space and drilled a three to put the home team up by one with just 1.2 seconds to go.

"Probably my biggest (shot)," Morris said, per ESPN. "I've hit a couple to tie it up. But was my first actual to win it."

Russell Westbrook missed a long-range three-point attempt at the buzzer and Boston came away with the win in dramatic circumstances to end the Thunder's six-game winning streak.

Morris finished with 21 points on 8-of-13 shooting to continue his impressive recent form.

The Celtics' triumph was even more remarkable given the fact that they were shorthanded again as the likes of Kyrie Irving, Jaylen Brown and Marcus Smart were sidelined.

In their absence, Tatum stepped up big and produced one of his best performances this season.

The 20-year-old posted a team-high 23 points and 11 rebounds and made big plays throughout the game for his team.

The young small forward has picked up the slack in recent games and head coach Brad Stevens says his role will continue to increase with several players out.

"We're going to just keep throwing him to the wolves and keep going to him in those moments," Stevens said.

Irving continues to deal with knee soreness and it's still unclear when he'll return so Stevens will need to continue using Tatum as the go-to guy and he's embracing the challenge.

The win doesn't change Boston's position too much as they're firmly locked into the number two spot in the east with a 48-23 record and are unlikely to claw back their five-game deficit on the Toronto Raptors.

But with a playoff berth already secured and their seed all but guaranteed, getting key players healthy should be the only priority for them now.

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