The Brooklyn Nets notched up a shock 119-116 victory over Milwaukee as the Bucks were forced to wait in their bid to clinch the Eastern Conference.
The two sides were fairly evenly matched as seventh took on first in the conference, but back-to-back three-pointers from Timothe Luwawu-Cabarrot within 30 seconds saw the Nets eke out a five-point lead with 2:30 to go.
Luwawu-Cabarrot had 26 points on the night while the Bucks' Giannis Antetokounmpo only played 16 minutes and had 16 points.
Other high seeds falling to lower opposition on Tuesday included the Los Angeles Clippers, who went down to the Phoenix Suns 117-115.
Devin Booker proved to be the difference, with a buzzer beater as time expired accounting for two of his 35 points.
Elsewhere, the Houston Rockets were downed by the Portland Trail Blazers 110-102, the Miami Heat saw off the Boston Celtics 112-106 and the Indiana Pacers defeated the Orlando Magic 120-109.
The day's other fixture saw Dallas boost their play-off hopes and dent those of the Sacramento Kings, with the Mavericks taking out a 114-110 overtime win.