PHOENIX -- Cody Ross hit a sacrifice fly to the warning track in left-center field and the Arizona Diamondbacks remained undefeated in six extra-inning games with a 3-2 victory over Colorado on Saturday.
A.J. Pollock opened the ninth off Edgmer Escalona with a single to left field, his third hit of the game, and stole second base on the second pitch to Miguel Montero. Pollock took third when catcher Wilin Rosario's throw went into center field and Montero was intentionally walked to bring up Ross.
Arizona (14-10) had its third walkoff victory of the season, and its eighth victory in its last at-bat. The D-backs have played 17 games that have been decided by two runs or fewer, the most in the major leagues.
Pollock hit his third homer of the season, his first homer since he had two homers and a double and drove in six runs in Arizona's 10-2 victory over Pittsburgh here April 10.
J.J. Putz (2-0) pitched a 1-2-3 10th inning after saving the first game of the series Thursday.
Rosario's sixth home run of the season and second in as many games broke the D-backs' shutout in the sixth inning. Rosario had three hits, adding two singles.
The Rockies tied it at 2 in the seventh when Dexter Fowler doubled and scored on Troy Tulowitzki's two-out single off Heath Bell. Tulowitzki was 1-for-18 off Bell before that at-bat.
Fowler, the Rockies' leadoff hitter, doubled and walked three times. Tulowitzki had two singles and walked twice.
Colorado (15-9) has lost five of its last seven games but still has a one-game lead in the NL West.
Josh Wilson had two hits for the D-backs.
Pollock hit his third home run of the season with one out in the first inning before Miguel Montero singled with two out and scored on Cody Ross's triple. Montero had three hits in his previous 27 at-bats.
D-backs starter Wade Miley walked four of the first five batters he faced in the first inning but did not give up a run. Carlos Gonzalez grounded into a double play after the first two walks, and Wilin Rosario struck out with the bases loaded to end the inning.
Miley walked a career-high seven in 4 1/3 innings and left with the bases loaded in the fifth before Brad Ziegler got Michael Cuddyer to ground into a double play to preserve Arizona's 2-0 lead.
Rosario's line drive homer into the left field seats to open the sixth cut it to 2-1
NOTES: D-backs shortstop Didi Gregorius, struck in the head by a Josh Outman fastball in the seventh inning Friday, passed cognitive and CT tests that night but was not cleared to play Saturday, D-backs manager Kirk Gibson said. "I don't think I would be close to normal right away," Gregorius said when asked his condition. "Probably take a couple of days, I think." He said he held no malice toward Outman. "I don't think he did it on purpose, so everything is good, everything is fine. There was obviously no reason. I already had two strikes," Gregorius said. ... Colorado manager Walt Weiss said the just got away from Outman, who was intending to throw it low and outside. "That's always really tough to see. I have a lot of respect for the career of every player in the league. We are all very sensitive to that. You never want to see a guy get hit in the head," Weiss said. ... Arizona outfielder Jason Kubel (quadriceps) was 3-for-4 with a home run in an extended spring game Saturday. Kubel is eligible to return from the disabled list Monday, but the D-backs plan to send him to Class AAA Reno on a rehab assignment Monday and Tuesday, with a target return date of Wednesday. "It could change if something happened with an injury or something," D-backs manager Kirk Gibson said. "He's kind of ready, but we 'd like to send him out and kind of confirm that." Kubel is hitting .333 with two homers in eight games this season.