Alexi Amarista backed Clayton Richard\'s 8 2/3-inning start with a homer and three RBI Monday, lifting the San Diego Padres to a 6-2 win over Arizona. Amarista got things going with a solo home run in the first inning and San Diego never trailed after. The Padres second baseman added a two-run double in the sixth for a 4-0 advantage. Cameron Maybin also went deep and rookie catcher Yasmani Grandal knocked his third homer in four major league games for the Padres, who took the opener of a three-game series. Richards (6-8) handled the Diamondbacks on two runs, allowing eight hits and one walk while striking out three. Joe Thatcher recorded the final out for his first career save. Trevor Cahill (6-7) was touched for four runs (two earned) on seven hits in a six-inning start for Arizona. Chris Young belted a solo homer for the Diamondbacks.