Welington Castillo's three-run homer in the eighth inning rallied Arizona to a 6-5 victory over the San Francisco Giants on Saturday night, ending the Diamondbacks' six-game losing streak.Castillo ripped reliever Hunter Strickland's 2-1 pitch into the stands in left field with one out. The Giants led 5-3 going into the inning, but starter Jeff Samardzija and reliever Josh Osich each put runners on base. UC Berkeley Sophomore Killed in Bangladesh Attack Strickland (3-1) replaced Osich and gave up the game's biggest hit. Jake Barrett (1-0) earned his first major league win in relief and Brad Ziegler got his 17th save of the season.Brandon Crawford and Mac Williamson hit back-to-back home runs to give the Giants a 5-1 lead in the fourth. Williamson's blast flew well over the 413-feet sign in left-center field and off the bottom left corner of the Chase Field video board. Dramatic Images: Militants Take Hostages in Bangladesh The Diamondbacks avoided their longest losing streak of the season. The Giants scored their first three runs in the second inning. Buster Posey walked, took third on a single and scored on a fielder's choice when Diamondbacks shortstop Jean Segura threw wide to...