The San Antonio Spurs took a 3-1 lead in the NBA Finals with another comfortable 107-86 road win over Miami, closing within one victory of avenging last year's loss to the Heat.
Kawhi Leonard had 20 points and 14 rebounds for the Spurs, who can win their fifth NBA championship with a victory at home in Game 5.
LeBron James tried to keep the Heat in it with 28 points and eight rebounds, but Dwyane Wade was just 1 of 10 through three quarters and finished with 10 points.
No team has overcome a 3-1 deficit in the finals, and the way they were outclassed twice on their home floor makes it hard to imagine the two-time champions being the first.
Tony Parker added 19 points, and Tim Duncan had 10 points and 11 rebounds for the Spurs, who shot 57 percent from the field.
The past 13 times Miami lost a playoff game, they always responded with a victory in the next encounter, but successive losses suggests they might be weary at the end of a fourth-straight season that has gone the distance.
The visitors were not quite as sharp as when they shot a finals-record 75.8 percent in the first half , but they were still good enough to open another huge lead by halftime, and they withstood every attempt Miami made to make a run.
The Spurs used a 13-2 spurt to open a nine-point lead, and that was the margin when they went to the second ahead 26-17.
San Antonio got the first five of the second to make it 31-17 on Danny Green's three-pointer, and the Spurs blew it open later in the quarter with seven straight points, capped by Leonard's soaring follow dunk that made it 55-33.
It was another rough start for James, who battled cramps in Game 1, then left the court and briefly returned to the locker room midway through the first quarter.
He had 10 quick points in the third quarter to bring Miami within 13, but San Antonio got a basket from Duncan to start a 7-0 run that pushed it to 68-48. The Spurs poured it on late in the third, pushing the lead to 81-57.