DETROIT (AP) - Prince Fielder homered for the first time in three weeks, hitting a two-run shot in the first inning to help the Detroit Tigers to a 4-1 victory over the Kansas City Royals on Thursday night. Andy Dirks added two doubles and two singles for the AL Central-leading Tigers, who took the opener of this five-game series with third-place Kansas City. The Royals have lost three in a row after a 17-3 stretch that put them in contention for a postseason spot. Detroit's Anibal Sanchez allowed a run and seven hits in 7 1-3 innings. Bruce Rondon finished the eighth, and Joaquin Benoit pitched a hitless ninth for his 16th save in 16 chances. Jeremy Guthrie allowed four runs and 13 hits in seven innings.