Buck, Ryan Shealy and David DeJesus each hit a home run for the Royals, who have won five straight and six of their last seven.

Brandon Duckworth (3-1) held the Mariners to just two runs on five hits through six innings to get the win.

Jose Lopez was 3-for-4 with a home run and two runs scored and Jeremy Reed had two RBI for the Mariners, who have lost six straight and seven of their last eight.

Brandon Morrow (2-4) gave up six runs on eight hits in four-plus innings to take the loss.