Mike Yastrzemski hit a three-run homer as the San Francisco Giants defeated the Seattle Mariners 10-1 for their fifth straight win Wednesday night under skies turned orange by raging wildfires in Northern California. ''It was weird,'' Giants pitcher Tyler Anderson said. Mariners starter Nick Margevicius (1-3) struck out six his first time through the order before the Giants broke through in the bottom of the third of a scoreless game.