John Wall hit a three-pointer with 3.5 seconds left for the go-ahead basket before jumping on the scorer's table and yelling to celebrate Washington's 92-91 victory over Boston that pushed their NBA Eastern Conference semi-final to a game seven.
Wall overcame a one-for-12 start to finish with 26 points, and Bradley Beal led the Wizards with 33.
The backcourt mates combined for 23 of Washington's 26 points in the back-and-forth fourth quarter.
Isaiah Thomas and the Celtics showed up dressed in black, but couldn't back up the fashion statement, blowing an 87-82 lead over the last two minutes.
Thomas' heave at the buzzer clanked off the rim. He and Avery Bradley each had 27 points.
John Wall. Pic: Getty More
The series-deciding game seven is at Boston on Monday night, with the winner to face LeBron James and the Cleveland Cavaliers in the East finals starting on Wednesday.
The host has won all 10 games between the Wizards and Celtics this season - four in the regular season and six in the playoffs.
Boston, who won the last match of the series at home by 22 points, led game six by 69-66 entering the fourth quarter, when a relatively average game became much more compelling.
The final period was tight throughout, featuring six ties and nine lead changes.
After Bradley and Beal traded shots to even it at 89, the Celtics had the ball and, coming out of a timeout with 14.1 seconds remaining, Al Horford made a 16-foot bank shot for the lead.
After another timeout, Wall made the three that would decide the outcome.
When the buzzer sounded, he ran to a corner of the court, then made his way to the sideline, jumped up and yelled and popped his jersey.
Wall's teammate Bradley Beal (33) led all scorers, while Avery Bradley and Isaiah Thomas each scored 27 for the Celtics.
Boston will have home advantage in Monday's decider, with the Cleveland Cavaliers awaiting the winners of the TD Garden clash.