Luka Doncic scored 42 points with 10 rebounds but it was not enough for the Dallas Mavericks who suffered their sixth loss from their past seven games 129-122 to the Miami Heat on Saturday.
The win was much needed for Miami, who improved to 41-37 to be seventh in the East, with Jimmy Butler top scoring with 35 points and 12 assists at FTX Arena.
The Heat snapped their three-game skid but it left the Mavs' perilous playoff hopes worse off, falling to a 37-41 record, remaining 11th in the West.
Dallas are a game back from Oklahoma City (38-40) in the race for the final play-in spot, with the Thunder owning the head-to-head tiebreaker too.
Doncic tried his best with 42 points on 17-of-25 shooting with two triples along with 10 rebounds, eight assists and two steals. That was the Slovenian's 14th 40-point game this season.
Kyrie Irving added 23 points and eight assists, while Tim Hardaway Jr drained six three-pointers in his 31 points with six rebound and seven assists.
Yet all that was not enough for Dallas who shot at 61 per cent as a team, after Miami piled on 44 first-quarter points, leaving the Mavs to lament their defense. Miami's 76 first-half points was the third most in franchise history.
Center Cody Zeller offered good support to Butler with 20 points and eight rebounds, while Kevin Love and Max Strus both added 18 points and Tyler Herro contributed 15.
Ingram stars as Pels continue playoffs push
The New Orleans Pelicans moved above the Los Angeles Lakers and into the seven spot in the Western Conference with a crucial 122-114 over the Los Angeles Clippers.
Kawhi Leonard scored 40 points for the Clippers, who fall to sixth in the West, but Brandon Ingram maintained his fine form with a game-winning display.
Ingram scored 36 points on 13-of-23 shooting with four rebounds and eight assists, while Jonas Valanciunas added 23 points with 12 rebounds.
Leonard shot 15-of-28 from the field with four-of-eight from beyond the arc with eight rebounds and four assists, while Russell Westbrook contributed 24 points with nine assists.
The Pels have won seven of their past eight games to shoot into playoffs contention in the West with a 40-38 record, while the Clippers are 41-38.