Boxberger, 30, was the Diamondbacks’ closer last season. He saved 32 games with a 4.39 ERA and a 71/32 K/BB ratio in 53 1/3 innings. The right-hander was an All-Star reliever in 2015 with the Rays, leading the league with 41 saves, but struggled to stay healthy in 2016-17.
Wily Peralta handled most of the scant save opportunities for the lowly Royals last season, accruing 14 saves with a 3.67 ERA an da 35/23 K/BB ratio in 34 1/3 innings. It is not clear yet if Boxberger will assume the closer’s role from Peralta or serve as the set-up man. According to MLB.com’s Jeffrey Flanagan, that will be cleared up by how each player performs in spring training.