The final six minutes devolved into a sideshow. The Knicks were playing, but they were basically spectators to anything happening.

Boston fans at TD Garden, celebrating ring night and an annihilation of the Knicks, went improv with a chant I’d never heard before in 14 seasons covering the NBA.

“One more 3!” the sold-out crowd repeated.

The Celtics couldn’t oblige. They somehow missed 13 straight 3-pointers to end the game, finishing with 29 makes to tie the all-time NBA single-game mark. Avoiding stand-alone embarrassment in the record book was the only Knicks triumph Tuesday.