San Francisco Giants pitcher Madison Bumgarner clubbed two home runs but it was not enough to stop the Arizona Diamondbacks snatching a 6-5 win in a thrilling season-opening duel. Bumgarner became the first pitcher in Major League Baseball history to hit two homers on Opening Day and looked to have helped the Giants into a game-winning position as they led 5-4 in the ninth. Earlier, Bumgarner hit bases-empty home runs in the fifth and seventh innings to put the Giants 4-3 ahead.