When shortstop Ian Desmond retrieved the ball and threw to first baseman Adam LaRoche, Alvarez was called out by umpire Laz Diaz, who ruled Alvarez had made a turn toward second base.
Hurdle came out of the dugout to protest the call, and he quickly got the boot from Diaz. It was the Pittsburgh skipper's fourth ejection of the season.
A few innings earlier, his counterpart, Washington's Davey Johnson, had been ejected by home-plate umpire Mike Winters for coming to the defense of Desmond, who was objecting to a called third strike.
Tom Singer is a reporter for MLB.com and writes an MLBlog Change for a Nickel. He can also be found on Twitter @Tom_Singer. This story was not subject to the approval of Major League Baseball or its clubs.