Hayes tripled and drove in two runs.The Royals had 18 hits, including seven doubles.
Lorenzo Cain, Jarrod Dyson and Miguel Tejada added two hits for Kansas City. The Mariners took a 4-1 lead before a six-run seventh for Kansas City.
Mariners starter Jeremy Bonderman gave up seven runs and 11 hits in 5 1-3 innings.
Franklin Gutierrez and Michael Morse homered for Seattle in the seventh.