Blake Snell struck out a career-high 15 in six innings in the San Francisco Giants’ opening 4-1 victory over the Colorado Rockies, and Hayden Birdsong fanned eight over five innings in a 5-0 win in the second for a doubleheader sweep Saturday night. Patrick Bailey hit a tiebreaking, two-run double in the seventh inning in opener. In the second game, Tyler Fitzgerald hit his eighth homer in 10 games. Snell had the most strikeout in the majors this season and the most for an outing of six innings or under since at least 1901. The reigning NL Cy Young Award winner struck out 15 of 18 batters. The Rockies struck out 30 times in the doubleheader.