Brandon Belt doubled to lead off the 18th inning and scored on Erik Kratz's one-out, fielder's choice grounder, as the San Francisco Giants beat the Colorado Rockies 3-2 Friday night. After Belt doubled and two batters were intentionally walked to load the bases, the Rockies went to a five-man infield, bringing in center fielder Ian Desmond. Kratz hit a slow grounder to Desmond, who had to run to his left before throwing home.