The fight occurred in the late stages of the first period and Simmonds made sure to remind Pezzetta why he's not only one of the most feared grinders/enforcers in the NHL, but why he's also one of the most respected. In the clip below, you can see how efficient Simmonds is with his punches, dropping Pezzetta with just 2 shots and a 3rd on the way down.
Naturally, Simmonds, being the class act that he is, didn't continue to swing once he had Pezzetta down, but again - that's why Simmonds is one of the most respected players of his ilk in the league.