Buster Posey and Evan Longoria both homered for the second straight game, and the San Francisco Giants took advantage of the Seattle Mariners' bullpen issues for a 6-3 win Friday night. Posey went deep leading off the third inning and Longoria added a two-run shot off starter Yusei Kikuchi in the sixth to tie it at 3. Posey pulled his homer down the left-field line on opening night and drove his second of the season out to deep right-center.