The San Antonio Spurs have set up an NBA finals series against the Miami Heat for a second year in a row after beating the Oklahoma City Thunder 112-107 in overtime to win the Western Conference finals.

Leading 3-2 going into the game, it looked like the Spurs had done enough to clinch the series in regulation as they headed into the fourth quarter 10 points ahead, led by Tim Duncan and Kawhi Leonard.

However, the Thunder fought back, with Kevin Durant briefly giving them the lead with 30 seconds still to play, but Manu Ginobili put San Antonio back in front before a late shot from Russell Westbrook sent the game to overtime.

Westbrook and Serge Ibaka got Oklahoma City off to a good start as they looked to keep the series alive in overtime, but Duncan and Boris Diaw found their rhythm in the last couple of minutes to take the Spurs through.

The Spurs will host the opening game of the finals on Thursday against the two-time defending champions.