Stephen Curry finished with 26 points as the Golden State Warriors beat the Los Angeles Lakers 115-113 to end their five-game winning streak.
Curry scored a three-pointer with 1:07 left before the Lakers' LeBron James missed a three-pointer at the horn.
Kevin Durant scored a key late three-pointer in his 30 points as Brooklyn Nets beat the Milwaukee Bucks 125-123.
James Harden, with 34 points, became the first Net to score 30 points in his first two games.
NBA's Most Valuable Player in 2018 joined the Nets from the Houston Rockets last week as part of a four-team deal.
That trade saw the Rockets acquire Victor Oladipo from the Indiana Pacers and he scored 32 points on his team debut at the Chicago Bulls, but the hosts ran out 125-120 winners with Zach LaVine scoring 33 points.
Bam Adebayo produced his fifth double-double of the season with 28 points and 11 rebounds to help the Miami Heat - without four key players because of Covid-19 protocols - rally to a 113-107 win over the Detroit Pistons.
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In Tuesday's other game, Kyle Lowry scored 23 points as the Toronto Raptors won 116-93 to hand the Dallas Mavericks their third straight loss.
It is the first time this season that the Raptors, playing at their temporary home in Tampa due to Covid-19 restrictions in Canada, have won three in a row.
The Washington Wizards game scheduled for Wednesday at the Charlotte Hornets is now postponed after six players tested positive for Covid-19.
It is the fifth match in a row over an eight-day span to be called off for the Wizards that has been called off as they are unable to send a minimum eight players on to the court under NBA health and safety protocols.
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