The relatively positive health status the Bulls have enjoyed during their first-round playoff series against the Nets thus far may have taken a turn for the worst. Kirk Hinrich, who had 18 points, three steals and tied a franchise playoff record with 14 assists in Saturday afternoon’s Game 4 win at the United Center, apparently suffered a calf injury during the triple-overtime thriller, in which he played a record-tying 60 minutes. “He got banged up a little bit,” Bulls head coach Tom Thibodeau said after the team’s film session Sunday afternoon at the Berto Center. “I think he got tangled up. It was just one of those things.” Thibodeau refused to go into any detail about the veteran’s ailment, calling it “just a bruise,” and not clarifying the starting point guard’s status for Monday night’s Game 5 in Brooklyn. “I don’t want to jump to any conclusions,” the coach said. “We’ll see where he is tomorrow.” In a more positive development, All-Star center Joakim Noah, who played nearly 40 minutes Saturday—his minutes restriction prescribed a maximum of 30—had no immediate repercussions from his heavy workload.