Chicago star Derrick Rose returned from a one-game absence brought about by an ankle sprain, but he was ineffective while playing only 25 minutes and was not on the court during the overtime period.
The Bulls made it into overtime thanks to a 3-pointer by Watson with 2 seconds left in the fourth period. LeBron James had a chance to give Miami a four-point lead with 11 seconds to go, but he could make only 1-of-2 from the foul line.
Chicago then produced nine of the first 10 points scored in the extra period. Kyle Korver's 3-pointer gave the Bulls a 10-point lead with 1:03 left. Miami managed only two points in the extra 5 minutes.
Miami has lost two in a row and three out of four, falling four games behind Chicago for the best record in the Eastern Conference. The Heat blew a 10-point lead late in the third period.