In several games during the postseason, Nate Robinson has been the Bulls’ savior. The diminutive instant-offense scorer has carried the short-handed team with his flurries of offensive firepower, lifting them to victory or at least staying in contention. But in Monday night’s Game 4 of the Eastern Conference semifinals, Robinson’s luck ran out. The scoring point guard was scoreless, shooting 0-for-12 from the field, including five misses from 3-point range and four turnovers, in the Bulls’ 88-65 shellacking at the hands of Miami. “They were very aggressive and Nate had a tough game. Nate’s a tough guy, he’ll bounce back,” Bulls head coach Tom Thibodeau explained. “He didn’t make shots tonight, but he’s a shot-maker and our team didn’t shoot well. We were 2-for-17 from three. You’ve got to make shots against these guys. So we’ll regroup, watch film and get ready for the next one.” One possible reason Robinson struggled was a left-shoulder injury that he didn’t want to discuss, but clearly bothered him, which was evident by the large wrap he had around it in the locker room. “Who knows, man? I don’t know. I don’t care,” Robinson said, when asked specifics about the injury. “It just happened today. But that doesn’t matter.