The swingman scored 21 of his 37 points during the fourth quarter to hold off a comeback from the two-time defending champions.
The 24-year-old told reporters: "I just felt it. I felt in rhythm. I had to be aggressive. I tried to come out and be aggressive to start this game off, and I was getting looks. I got hot."
The Pacers will need to win again tomorrow to take the series to a deciding seventh game.