The tradition began with the New York Giants football team in the mid-1980s. According to several sources, including Jim Burt of the Giants, it began on October 28, 1984, when the Giants beat the Washington Redskins 37 -- 13, and Burt performed the action on Bill Parcells after being angry over the coach's treatment of him that week. Burt insisted that Harry Carson dumped the Gatorade on Parcells, because Carson was a favorite and would n't get in trouble. Former Chicago Bears defensive tackle Dan Hampton claims he invented the shower, also in 1984, when the Bears dunked Mike Ditka upon clinching the NFC Central -- but that took place a month later in November. The phenomenon gained national attention in the 1986 Giants season. Parcells was doused after 17 victories that season, culminating with Super Bowl XXI.

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The relevant information is: The tradition began with the New York Giants football team in the mid-1980s. So, the answer is with the New York Giants football team in the mid-1980s.