Wesley Matthews tipped in a basket with 1.8 seconds left and Indiana rallied from a 19-point deficit to beat the Oklahoma City Thunder 108-106. Damontas Sabonis added 26 points against this former team.
Paul George shrugged off resounding boos to score 36 points, and Russell Westbrook, who added his 27th triple-double of the season but missed a 3-pointer from beyond the top of the key as the buzzer sounded.
Westbrook finished with 19 points, 14 rebounds and 11 assists.
George turned the ball over twice, slipped as the Pacers started their final possession and got knocked to the floor on a pick - giving Indiana the one-man advantage that allowed Matthews to free himself for the putback on Bojan Bogdanovic's errant 16-footer.
Matthews finished with 16 points and seven rebounds to help Indiana cut its magic number for clinching a playoff spot to one.
The Pacers' second straight win also kept them in third place in the Eastern Conference while the Thunder slipped into a tie for fifth in the West.
Steven Adams had 17 points and eight rebounds.
Darren Collison had 17 points, six rebounds and seven assists.
Bogdanovic scored 23 points.
The Pacers begin a crucial four-game road trip at Denver on Saturday.