Jokic rescued Denver after the Nuggets trailed by 12 early in the fourth quarter. He finished with 11 points, 14 rebounds and eight assists, hitting all four of his field goals in the fourth.
Luka Doncic led Dallas with 24 points. He had a go-ahead dunk with 5.8 seconds left, but Jokic topped it by leaning to his right and letting a shot go before the buzzer.
Paul Millsap finished with a season-high 33 points for the Nuggets (45-22), who strengthened their hold on the No. 2 spot in the Western Conference.
The team was scheduled to leave Dallas on Wednesday afternoon but Denver International Airport canceled flights in and out due to poor weather and forced the Mavericks to fly into Denver on Thursday morning. The team left Dallas at 8 a.m. and arrived in Denver at 9 a.m.
The Mavericks looked like the team with more energy, building an eight-point lead in the first half and ending the second quarter on a 13-2 run to take a six-point lead at the break.
Denver came out strong in the third quarter, but Dallas responded with eight straight points and led by as many as 12.
The Nuggets used a 12-2 run in the fourth quarter to get within 93-91. Jokic, who was 0 for 4 from the floor in the first three quarters, hit a layup to get Denver within a basket. Millsap tied the game at 95, and a free throw by Jokic with 1:06 left gave the Nuggets a 98-97 lead with 1:06 left.
Brunson missed a baseline jumper but a Denver turnover with 20.3 seconds left gave Dallas the ball and set up the final sequences.
Mavericks: F Kristaps Porzingis was with the team a day after taking part in his first 5-on-5 practice. Porzingis, acquired from New York on Jan. 31, has not played since tearing his ACL last season.
Nuggets: Torrey Craig was out with a left shoulder sprain suffered Tuesday night. Craig was hurt in the last 20 seconds of mop-up time. … F Trey Lyles was active after missing nine games with a left hamstring strain.
Mavericks: Hosts Cleveland on Saturday night.
Nuggets: Wraps up their three-game homestand against Indiana on Saturday night.