It's hard to imagine the Pittsburgh Penguins playing a worse period of hockey than they did in the first period against the New York Rangers in Game 1 of their second round series. Pretty much everything that could have gone wrong, went wrong, both because of their own play and because of things out of their control.
Late in the period Pittsburgh, with Sidney Crosby and Evgeni Malkin on the ice together, seemed to be having one of its better shifts of the period when this pass to Olli Maatta was whistled for being a hand pass. As this GIF (via @PeteBlackburn) shows, this play was clearly not a hand pass. Crosby did initially play the puck with his hand, but then clearly got his stick on it to pass it to Maatta at the point.
The officials had a brief conference and realized they made a mistake and called for a faceoff in the New York end of the ice instead of the neutral zone. Even that went wrong for Pittsburgh. After losing the ensuing faceoff and allowing the Rangers to clear the zone, Brad Richards found himself all alone in front of the net and scored to give the Rangers a 2-0 lead.
It's a bad call, but Pittsburgh has to respond better than it did.