The Kansas City Royals beat the Boston Red Sox, 7-3, on Thursday night. During the 7th inning, Royals catcher Salvador Perez hit a ball off the base of the foul pole that bounced into play. It was called a home run on the field and upheld on replay.
After the call, Red Sox manager Alex Cora went out to have a talk with home plate umpire Bill Welke, which is against the [written] rules of baseball because you're not allowed to argue replay decisions. Still, Welke politely heard Cora out. It certainly looked like Cora might avoid ejection as he spoke calmly and was smiling as turned to head back to the dugout. And that's when the hammer dropped.
Cora then spent more time and was much more animated while complaining about the unfair ejection than the home run call. Watching the video, the ejection seems almost unbelievable, but that's the beauty of baseball. A robot would have hit the ejecto seato cuz button the second Cora stepped on the field to question the call. Thanks to the human element we get to see an umpire play with the emotions of Cora before showing him the exit.