Travis Snider smacked a grand slam during a five-run sixth inning as the Pirates held on to clip the Cubs 5-4 in the opener of a three-game series at PNC Park. Pedro Alvarez walked in the other run for the Bucs, who have won two straight and six of their last seven. Wandy Rodriguez surrendered three runs over six innings to improve to 5-and-2. Jason Grilli gave up a run in the ninth but held on for his 18th save. Matt Garza permitted just one hit over five scoreless innings in his season debut. Garza, who has been sidelined with a strained left lat muscle, helped his own cause with a two-run double. Darwin Barney went 4-for-4 with an RBI and Starlin Castro also plated a run for the Northsiders, who have dropped two in-a-row and four-of-six overall. James Russell fell to 1-and-1 with the loss.