Duncan, who could decide to retire this summer, did not speak to the news media after the loss. It may end up being his last game at AT&T Center.

“It’s not over by any means,” the Spurs’ Danny Green said. “Stay positive. Bring the energy. We’ve won there before. We have to do it again or we’re going home, simple as that.”

Oklahoma City has made life tough for San Antonio, but every game, except San Antonio’s Game 1 victory, has been close. And after each game, it has been the same routine: dissecting some small play here, another minor call there, looking at various little things that might have influenced the result.

The referees, for instance, have been under the microscope. Spurs Coach Gregg Popovich does not often talk about officiating after the fact, but he said Tuesday that it was “obvious” that Leonard had fouled Westbrook in a late noncall situation, when the Spurs needed to foul. And he said he was “concerned” about a late foul call Durant had drawn, when it appeared that Green had been tripped into him.

“But every call doesn’t get called,” Popovich said. “That’s the way the game is.”

The Spurs have not quite looked like themselves. They had 39 assists in Game 1. They had 19 each in Games 2 and 3. After notching just 12 in their loss in Game 4, they had 19 again Tuesday. Popovich this week pointed out that game play, as a whole, tends to slow down during the playoffs. But he acknowledged the team needed to be sharper moving the ball.

After Game 5, the Spurs were ruing their inability to rebound. The Thunder beat them in that category, 54-36.

“That’s hurt us through the entire series,” Popovich said.

The Spurs have struggled of late to find good shots. LaMarcus Aldridge has symbolized the downturn. He made 33 of 44 field-goal attempts through the first two games, scoring 79 points, while confounding the Thunder with his one-on-one moves. In Games 3, 4 and 5, though, he faded, making only 22 of 60 shots and totaling 64 points.