Two teams that got roughed up by the Los Angeles Dodgers last week get an opportunity to vent their frustrations on one another when the Colorado Rockies and San Francisco Giants open a three-game series in San Francisco on Monday night. Colorado right-hander Jon Gray (7-5, 4.18 ERA), who has never beaten the Giants, and San Francisco lefty Drew Pomeranz (2-7, 7.09), who has never lost to the Rockies, are scheduled to go head-to-head in a matchup of clubs that suffered walk-off losses on the road Sunday. Pomeranz pitched in a 3-2 home win over the Rockies in April, although he did not get a decision after throwing five effective innings.