With Jake Sanderson laying on the crease, the referees blew the whistle. While it appeared everyone in the arena heard the whistle, except for Jeff Skinner. As the puck comes across to Skinner the whistle blows and Skinner fires the puck. The Senators immediately reacted exactly how you'd expect.
In Skinner's defense, the whistle probably shouldn't have blown as the Sabres still had the puck at the time. For his troubles Skinner received 2 minutes for roughing and 2 for unsportsmanlike conduct, while Travis Hamonic received 2 minutes of his own for roughing.