Danny Ainge revealed on Thursday that the Boston Celtics held discussions with Rajon Rondo about a contract extension, adding the team still plans to keep the All-Star guard. “We did talk to Rondo about extending him,” Ainge said. “But that’s all part of the negotiation that will happen again this summer and most likely the summer after. I don’t know [if he will sign an extension], time will tell.” “In the Collective Bargaining Agreement, there are limits on what can and can’t be done.