The Spurs’ inability to hold on to a 12-point lead in the final 1:35 of regulation Tuesday could prove to be costly. Manu Ginobili made the winning layup in the Spurs’ 110-108 overtime victory at Memphis, then spent the final 1.8 seconds on the bench stretching out his hamstring. Ginobili said his leg began tightening late in the game, in which he logged a season-high 32 minutes. He took himself out for the Spurs’ final defensive possession, which ended when Mike Conley missed a 29-footer. “I didn’t want to take any chances,” Ginobili said.