Miami's beaten Chicago 101-93 in overtime to take a 3-1 lead in American basketball's Eastern Conference finals and move one win away from a place in the NBA finals series.
A compelling, physical game in Miami finished 85-85 in regulation time after the league MVP Derrick Rose missed a game-winning shot for the Bulls with the final play.
The Heat dominated in overtime, LeBron James finishing with 35 points as they extended their post-season home record to 8-0.
It's the first time this season the Bulls have lost three successive games.
Game five in the best-of-seven series is in Chicago on Friday.
Dallas leads Oklahoma City 3-1 in the western conference series.
