The Rangers are 2 for38 on the power play this postseason.Forward Brad Richards will be a healthy scratch for Game 4 after posting just one goal for the Rangers in 10 postseason games. The former Conn Smythe winner has been a disappointment after signing a nineyear, $58 million deal with New York prior to the 201112 season.The Rangers haven't been swept in a playoff series since going down in four games to the Devils in the opening round of the 2006 postseason.Boston's last sweep came in the 2011 conference semifinals against the Flyers.The Bruins have played the first three games of this series without defensemen Andrew Ference, Wade Redden and Dennis Seidenberg, all of whom are battling injuries. Seidenberg and Redden made the trip to New York and are both questionable for Thursday's contest.."I would say I'm 100 per cent," he said recently, "But you can't put a number on it." And then he proceeded to, well, put a number on it. "No one ever knows when the