'Gave this game away': Brutal heartbreak for NBA underdogs in OT ...

The Boston Celtics have survived a big scare in Game 1 of their Eastern Conference Finals series, winning 133-128 in an overtime thriller against the Indiana Pacers.

It was a heartbreaking result for the Pacers, who fought back from an early 12-0 deficit and were just one possession away from likely taking the game and homecourt advantage.

Instead, the Pacers will need to put Wednesday’s result behind and regroup ahead of Game 2 on Friday.

All five of Indiana’s starters finished on double figures with Tyrese Haliburton recording 25 points and 10 assists while Pascal Siakam had 24 points, 12 rebounds and seven assists.

On the other side of the floor, Celtics star duo Jayson Tatum (36 points, 12 rebounds) and Jaylen Brown (26 points, seven rebounds) combined for 62 poinbts while Jrue Holiday had 28 points to go with seven rebounds and eight assists.

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The Celtics finished the first quarter up 34-31, having initially led 12-0 after the Pacers shot 0-for-5 from the floor early before rallying on the back of crucial bench production, with Obi Toppin (11 points) particularly efficient.

Boston, meanwhile, had Tatum and Brown combined for 18 points in the first quarter.

It was a different story in the second as the pair put up seven points between them while Myles Turner had 12 points and two assists in the quarter to continue inspiring a Pacers fightback.

A deep 3-pointer from Haliburton with 2.2 seconds left on the clock tied the game at 64-all heading into halftime.

By that point both teams were shooting over 50 per cent from the field, with Indiana sitting at 58.7 per cent while also going 53.3 per cent from downtown.

Haliburton opened the third quarter by scoring the first five points to put the Pacers ahead before the Celtics quickly responded with a 6-0 run of their own to re-gain the lead.

Boston was then able to push it out to 92-81 with just over two minutes left in the period and Indiana at risk of slipping away after doing so well to get back in the game in the first place.

But as they had all night, the Pacers battled back with nine straight points and ended the quarter on a flurry as a T.J. McConnell jumper and Haliburton 3-pointer closed the margin to 94-93.

The game hung in the balance right until the very end of regulation, with the Pacers leading 117-114 until a costly turnover from Andrew Nembhard gifted the Celtics one final possession to tie it up.

They did just that as Brown drained a clutch 3-pointer that sent the game to overtime and it ended up being a sign of what was to come as turnovers proved Indiana’s undoing.

The Pacers led 123-121 with just over 90 seconds left in overtime but quickly found themselves trailing 127-123 after a Haliburton turnover led to a Tatum 3-pointer.

Indiana called a timeout at that point but turned the ball over on the ensuing possession and gave up a layup to Derrick White that put Boston ahead 129-123 with 25 seconds left.

It was a matter of playing the foul game from that point as the Celtics held on.

Pacers coach Rick Carlisle later admitted in his post-game press conference that he should have taken a timeout in the final 10 seconds to advance the ball.

“This loss it totally on me,” he said.