About 600 workers have walked off the job at Maple Leaf Sports and Entertainment, a move that affects the restaurants, but not the games at the Air Canada Centre in Toronto.
The workers are represented by Teamsters Local 847, and are mainly kitchen, housekeeping and serving staff.
They are also responsible for changing over the arena from a basketball court to a hockey rink.
The workers voted 82 per cent in favour of job action after rejecting a deal that was reached after six months of negotiation.
The Toronto Raptors were playing against the Philadelphia 76ers on Friday night and the Toronto Maple Leafs are to play Saturday night.
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