The other night, Mikhail Sergachev, of the Lightning, was skating near Michael Bunting, of the Maple Leafs, at center ice. Upon skating next to Bunting, Sergachev decided to give a love tap to Bunting's arm, but it definitely wasn't just a love tap.
There is nothing but skin and bone on that part of the arm, and there isn't padding there either. So, with a solid object, like a stick, a slash like that is going to hurt a lot.
The slash went uncalled in the game, but thanks to video, the NHL Department of Player Safety was able to evaluate what happened and give Sergachev a pretty hefty fine of $5,000.
Don't slash someone over the arm and you won't be losing $5,000...simple as that.