Back in the first quarter, the Spurs lost a sizeable lead when Tim Duncan picked up his second foul. The Spurs went small, but none of their backup big men were legitimate threats to score, allowing the Thunder to cheat off them and seal off driving lanes. That led to a bunch of Spurs turnovers and a big Thunder lead.
Well, it happened again in the third quarter. With four minutes and 23 seconds remaining, Duncan picked up his fourth foul. At that point, the Spurs were up three. From then on, the Thunder outscored the Spurs 15-3.
The Spurs desperately need Duncan on the floor if they want to have any chance to win. Can he play the full fourth quarter? Can he stay out of foul trouble? That might be what it takes.