Even in the fiercest of rivalries, there are some lines not meant to be crossed.

A Toronto Maple Leafs fan may have done just that on Monday, however, by bring a “Toronto Stronger” sign to the Air Canada Centre for Game 3 of the Toronto-Boston series. The sign is ostensibly one-upping or mocking the “Boston Strong” mantra that the city embraced in the wake of the Boston Marathon bombings, which would make it inappropriate at best.

Check out a photo of the sign below.


Photo via Twitter/@nicklachey_10