According to NJ.com, when Astros starter Zack Greinke was warming up ahead of his start in ALCS Game 4, fans were taunting him in the bullpen, when one fan overstepped the line.
The Yankees fan was reportedly taking verbal shots at Greinke, who has battled social anxiety disorder and depression. New York police officers saw what was going on and intervened, reportedly ejecting the disorderly fan. Read more here: https://www.nj.com/yankees/2019/10/chaos-crude-yankees-fans-taunt-astros-zack-greinke-before-alcs-game-4.html