The Pacers steadily built as much as a 10-point lead in overtime to win for the 10th time in 11 games this season.
George led the way with 35 points and took advantage of a mistake by Iman Shumpert at the end of regulation.
Shumpert fouled George on a 3-point attempt with the Pacers trailing by three. George hit all three attempts and then scored nine of Indiana's 14 points in the extra period. He touched off the overtime by hitting a 3-pointer.
George Hill added 23 points for the Pacers and grabbed eight rebounds.
New York has lost four in a row and six straight at home. Carmelo Anthony scored 18 points along with 18 rebounds for the Knicks.