Orlando led by as many as 23, but Detroit kept its starting unit in late in the preseason game and closed the gap.
Tobias Harris, who sat out the Magic's previous two games, scored 13 points and connected on all three of his 3-point attempts. But he left late in the third quarter with soreness in his left ankle and did not return.
The Magic closed the first half with a 20-5 run.
A road trip to Toronto has put Cleveland in a precarious spot, as the Raptors have shaved away the Cavs' margin for error in tying the series.
After being left for dead after the first two games of the Eastern Conference Finals, the Raptors follow up a big Game 3 victory with an equally impressive win in Game 4 to tie the series heading back to Cleveland.
LeBron James discusses the Cavaliers awful second quarter and how they can't allow themselves to fall so far behind.