Doncic, who scored a franchise-best and season-high 60 points two nights earlier, recorded his eighth triple double of the season, finishing with 35 points, 12 rebounds and 13 assists.
The Slovenian guard led the Mavs to their fifth straight win, notching up a second straight triple-double for the second time this season. Doncic's collective 95 points across the past two games is an NBA-record in consecutive triple-doubles.
Doncic shot 11-of-21 from the field, including four-of-nine from beyond the arc, making nine-of-12 free-throws.
Ex-Rockets forward Christian Wood offered good support with 21 points, including five-of-eight three-pointers, six rebounds and four blocks, along with Dwight Powell, who added a season-high 19 points with six rebounds and two blocks off the bench.
The Rockets, who are 10-25 and have lost seven of their past eight games, had few answers as they fell behind 65-51 at half-time with a Doncic 35-foot buzzer beater, with Jalen Green top scoring with 23 points.
The NBA-best Celtics (26-10) had suffered their worst loss of the season at the hands of the Clippers earlier this month, losing 113-93, starting off a run where they lost five of six games.
Tatum had 11 rebounds to go with his 29 points, shooting 10-of-26 from the field, while Kawhi Leonard scored 26 points with eight rebounds for the Clippers.
Hield makes history in Pacers' win
Buddy Hield made history with the fastest three-pointer recorded since play-by-play began in 1996-97 as the Indiana Pacers downed the Cleveland Cavaliers 135-126.
Hield, who leads the league in three-pointers made this season, swished a shot just three seconds into the game. The Pacers made 19-of-31 from beyond the arc for the game, rallying from a seven-point fourth-quarter deficit.