Watch: Jayson Tatum stuffs Indiana's comeback attempt

With the Celtics clinging to a 127-124 lead in the final minute, Tatum rejected Myles Turner in the lane for a game-saving block. The result was a shot clock violation. On the next possession, Tatum blocked a layup attempt by Aaron Nesmith.

Boston racked up three blocks in the final 31 seconds, including Derrick White's athletic rejection of a Nesmith 3-point attempt. The game ended 129-124, with the Pacers going scoreless in the last minute.

It was a marked contrast from the second and third quarters when Boston allowed 77 points. The Celtics clamped down in the final 12 minutes, holding Indiana to 21 points, which was crucial when their offense bogged down.

In the final seven minutes, Boston made only one shot from the field in eight attempts. They did shoot 7-of-8 from the foul line, but for a matchup between the two top teams in offensive rating, it was remarkably tough for either team to score late.

Especially on Tatum. He had two blocks, while his team had nine in total. Indiana had just two, and that was the difference in what could be a playoff preview.

The other takeaway from this game is that the Celtics offense looks very ordinary when their threes aren’t falling. Going into the fourth, Boston had shot 15-of-27 behind the arc (55.5 percent). In the fourth, it was 2-of-9, with no triples in the final eight minutes.

But when the Celtics’ shots went cold, their defense heated up and swatted the Pacers away.