The former No. 1 overall pick had 19 points and the deciding defensive play in a 125-121 victory over the Washington Wizards on Sunday night.
Nikola Vucevic had 30 points and 17 rebounds and Evan Fournier added 25 points and nine assists, but the Magic nearly squandered an 18-point fourth quarter lead before Fultz stopped Washington's rally.
Fultz made all six shots from the field in the first half, including a pair of 3-pointers, and finished 8 for 10 from the field. However, it was his defensive play that decided the game.
With Orlando leading 119-116, Fultz stole a pass and was fouled as he dunked the ball with 36.1 seconds left. His free throw finished the 3-point play and gave Orlando a six-point cushion that stood up for the team's fourth win in its last five games.
"That was definitely fun," said Fultz, who was drafted No. 1 by Philadelphia 76ers in 2017 before being traded to Orlando midway through last season. "You live for moments like that when the game is on the line and you're out competing to see what everybody is made of. I love it that I got a chance to make a big-time play and I finished it off."
Orlando needed it to withstand a couple of fourth-quarter rallies by Washington and its 3-point shooting team. The Wizards made 10 of 15 3-pointers in the final period and scored 44 points, but couldn't play enough defense to overtake Orlando.
"We are 10 games in (to the season) now so we have to dial back the amount of excuses we have," Beal said. "We compete hard enough to win every game. We are top five on offense, so we know that's not the problem. We just have to get stops."
The Magic had to put down two furious rallies from the Wizards in the fourth quarter. Washington was down 95-78 early in the fourth quarter, but closed to within 97-91 on a 3-pointer from Moritz Wagner with 7:23 left in the game
Wizards: Washington missed its first seven 3-point attempts. ... Beal limped away on his ankle after a drive to the basket in the first five minutes of the game but returned with no apparent ankle problem. ... Reserve C Moritz Wagner, who had a history-making 30-point, 15-rebound performance in his last game, followed it up with 12 points and three rebounds.
Magic: F Jonathan Isaac missed his second straight game with a sprained ankle. ... Reserve G Michael Carter-Williams left the game at the 10:50 mark of the second quarter with a hip injury. D.J. Augustin left six minutes later with a dislocated finger, but did return. He finished with 13 points.
Wizards: Host San Antonio on Wednesday night.
Magic: At Toronto on Wednesday night.
Biggest trade, free-agency and draft decisions for every eliminated NBA team
ESPN Insider Bobby Marks breaks down the moves each team can and should make in the offseason.
NBA playoffs: What sets Nikola Jokic apart from other NBA superstars
Nikola Jokic is a surprising NBA superstar. Here are the ways his path, success and skills are so unusual.
Kemba: Celtics learned from first two losses to Heat
Kemba Walker breaks down the Celtics' Game 3 win over the Heat, saying they learned from their first two losses in the series.