The Royals scored two unearned runs in the seventh inning thanks to Florimon's miscue, resulting in Kansas City's eighth straight win.
It was a 2-2 game in the seventh and the first two Kansas City batters in that inning were retired by Caleb Thielbar.
Alex Gordon then tripled and Hosmer followed with his fateful ground ball to Florimon. When the Minnesota shortstop failed to play the ball cleanly, Gordon came in with the go-ahead run. Hosmer then stole second and scored on a Billy Butler single.
Jeremy Guthrie (11-7) benefited from the unearned runs to pick up the victory. He allowed two runs on six hits through six innings. Greg Holland struck out two in the ninth on the way to his 28th save.
Thielbar (1-1) was charged with the loss, the first of his major league career in 25 relief appearances.
Minnesota has lost three in a row.