my vote is for Gerald Henderson - Game 2 1984 Finals vs Lakers
why ?
unlike the others, that play was made in the finals and led directly to a win that led to a title. without that steal, the celts probably lose that series.
Havlicek's steal is my 2nd because it wins a huge game in the playoffs that helped the Celts win another title.
Bird's steal was probably the best play of the bunch because all hope was lost in that game just 2 seconds prior to Bird's play ....... and for him to hang in there and then step in from nowhere to steal the ball off the hands of (sorry to saay) another hall-of-fame player was amazing. but we didn't win the title that year - that fact takes just a little shine off the win - but i hated those Pistons so much, thank god for Larry.
here's hoping that Rondo's steal contributes to another title - it was a great play and helped win a very important game in a series in which the Celts were decided underdogs going in. let's win game 7 tonite and put that steal in special place in Celtics history.