There have been some wild interactions over the years between players and fans, and while this isn't Mike Milbury with the shoe or Tie Domi in the penalty box wild, it's still pretty wild.
During a game between the New York Yankees and Cleveland Guardians, Guardians outfielder Steven Kwan ran into the left field wall. While he was down and being checked on by medical personnel for a concussion, some Yankees fans chose to taunt him.
The reported taunts were simply, "stay down Kwan!" But this set off his teammate, Myles Straw who immediately climber the left field fence and confronted the fan.
Confirmation of what was initially said, but this video has been released of the heated altercation. While I understand wanting to protect your downed teammate this seems like a disproportionate response.