Johnson was upset that DiPietro took a high shot at Matt Cooke, with seconds left to go in a game that's outcome was decided. A staple of Penguin hockey is any player standing up for any other player, and this trend continues as Johnson skates the length of the ice, side steps a ref and then delivers a one-punch message to the offending goalie.
Video after the jump...
Interestingly, Johnson was mere seconds away from what surely would have been a shutout. Due to the fights, Johnson got tossed from the game and Marc-Andre Fleury had to come in and mop it up. According to the NHL, a goalie must play the full 60 minutes to be accredited with a shutout, so Johnson won't get the statistic in his personal stat-sheet.
Something tells us though the respect and admiration he earned from every person in the Penguins organization sure beats that.