http://www.dispatch.com/content/stories/local/2015/01/10/proathletes-sue-ohio-cleveland-over-taxes.html
Summary:
Ohio State law allows out-of-state people to work in Ohio for 12 days each year before they are subject to Ohio state income tax.
The law excludes entertainers and professional athletes.
So, if Buffalo plays in Cleveland, everyone on the team has 1/16 of their income become subject to Ohio taxes. This includes players, coaches, support staff, etc.
The City of Cleveland also has a City income tax on visiting teams. This tax applies to everyone on the team, including injured players and practice squad player who didn't even travel to the game.