The Pacers, who were on a seven-game winning streak in the NBA, were defeated in the last second by a Cavaliers side who are struggling at the bottom of the Eastern Conference after losing LeBron James in the off season.
Nance Jr had 15 points on the night and 16 rebounds, his most important coming when he tipped in a missed Rodney Hood shot when the Cavs trailed by one in the last second.
Indiana could have put the game out of reach of the Cavs, but Victor Oladipo missed two free throws with less than 10 seconds left.
The Brooklyn Nets took their winning streak to six games with a 115-110 win over the Los Angeles Lakers.
D'Angelo Russell scored 22 points against his former side , while Lakers star James scored 36 points and had 13 rebounds in a losing effort.
Elsewhere, Nikola Jokic's 32 points helped the the Denver Nuggets beat the Dallas Mavericks 126-118, while the Atlanta Hawks beat the Washington Wizards 118-110.