The Golden State Warriors are on the brink of their third NBA championship in four years after winning 110-102 away to the Cleveland Cavaliers to take a 3-0 lead in the best-of-seven series.
Kevin Durant, who top scored with 43 points, sealed the win with a three-pointer with 49.8 seconds remaining.
LeBron James led the home side with 33 points, 10 rebounds and 11 assists.
Golden State will secure the title if they win game four on Friday night, again in Cleveland.
"That was amazing what he did out there tonight," said Warriors coach Steve Kerr of Durant. "Some of those shots, I don't think anybody in the world can hit those but him."
No team has ever come back from a 3-0 deficit to win a series.
Cleveland raced into a 16-4 lead in the first half, the highlight being James throwing a pass to himself off the backboard and finishing with a dunk.
They led by six at half-time, but the Warriors grabbed the initiative in the third, outscoring the Cavaliers 31-23 to take an 83-81 lead into the fourth quarter.
The final quarter was a tight affair until Durant won the game in the final minute.
Stephen Curry, who set a new NBA record in game two, suffered a rare off night with 11 points.
Last year Golden State, the defending champions, were also 3-0 up against the Cavaliers, and although they lost game four they secured the title in game five.
After some contentious calls in the first two games, the official Twitter account of the NBA referees tweeted during game three to confirm James' pass to himself off the backboard was legal.