The Los Angeles Lakers lost for the first time in 10 matches as they were edged out by the Orlando Magic 119-118.
LeBron James's side have a commanding lead at the top of the Western Conference but it was the Magic who took the initative in the second quarter, extending the advantage to 51-31 at one stage.
Quinn Cook had 22 points for the Lakers while James added 19, but it was Markelle Fultz (21 points) who got the key scores, a pair of two pointers in the last minute securing the win for Orlando.
Kendrick Nunn scored 33 points as the Miami Heat saw off the San Antonio Spurs 106-100 to move into second place in the Eastern Conference.
The Spurs had a three-minute scoring drought to start the fourth quarter as the Heat took the lead and held on to improve their home record to 18-1.
James Harden only scored 13 - his lowest total since January 2018 - as the Houston Rockets fell to the Portland Trail Blazers 117-107, while Luka Doncic hit a triple-double with 25 points, 15 rebounds and 17 assists in a 127-123 win for the Dallas Mavericks over the Sacramento Kings.
?? the BEST DIMES from @luka7doncic's career-high 17 AST in the @dallasmavs win!— NBA (@NBA) January 16, 2020
Doncic (25 PTS, 15 REB, 17 AST) becomes the youngest player in @NBAHistory to record a triple-double with 15+ REB & 15+ AST. #MFFL pic.twitter.com/eI1CYiEOqA
Elsewhere, Tobias Harris scored 34 and Ben Simmons poured in 20 as the Philadelphia 76ers saw off the Brooklyn Nets 117-106, the Detroit Pistons won for the first time in four outings to secure a 113-103 success against the Boston Celtics and the Indiana Pacers pipped the Minnesota Timberwolves 104-99.
Zach LaVine was among seven Chicago Bulls to record double-figures as the side defeated the Washington Wizards 115-106, the Toronto Raptors edged past the Oklahoma City Thunder 130-121 and rookie Michael Porter Jr scored 19 points in the Denver Nuggets' 100-86 win over the Charlotte Hornets.