DENVER — Madison Bumgarner has endured more than his share of bad luck in a season full of misfortune for the Giants.
"I feel like I have been through a tough stretch," Bumgarner said. "We talk about things like this and there is always the feeling that thing would come around."
It didn't on Wednesday night.
Jhoulys Chacin did not allow a hit for 6 2-3 innings and hustled for a crucial RBI to help the Colorado Rockies beat the Giants 5-4.
"The defense got us the one inning," San Francisco manager Bruce Bochy said. "We did come back and I thought we were going to pull it out there," but we came up short."
Bumgarner (11-9) was effective until the sixth. He allowed just three hits, including Nolan Arenado's RBI double in the second before Colorado tagged him.
Chacin (13-7) tied a season high with nine strikeouts. Brandon Crawford's single to center field was the only hit Chacin allowed in seven innings.
"I knew he had a no-hitter going," said Crawford, who singled on a 1-2 pitch. "It was nice to get us on the scoreboard."
Chacin, who yielded an unearned run, retired Roger Kieschnick to end the Giants seventh.
"Chacin has good stuff," said Brandon Belt, who drew two walks off him. "He doesn't leave anything really in the middle. He nibbles around a little bit and makes you go after his pitch."
Troy Tulowitzki and Wilin Rosario had two hits each for Colorado, which built a 5-1 lead through six innings.
DJ LeMahieu led off the inning with a single, Tulowitzki walked and Rosario hit a bloop single to center to make it 2-1.
Jean Machi entered and got Arenado to hit a comebacker, but Crawford dropped the throw to second to load the bases. Yorvit Torrealba's ground-rule double made it 4-1, and after an intentional walk, Chacin beat out a potential double-play ball at first for another run.
The Giants nearly left Chacin with a no-decision when they rallied for three runs in the eighth. Belt hit an RBI double, Buster Posey drove in another run with a groundout and Pence singled to make it 5-4.
Rex Brothers worked the ninth for his 14th save.
While Chacin was baffling the Giants, the defense behind him was suspect.
Rosario, starting at first base for the third time this season, mishandled two straight grounders to start the third. Chacin got Bumgarner to pop up a bunt attempt, struck out Gregor Blanco and got Marco Scutaro to ground out to end the inning.
The Giants capitalized in the fourth. Belt walked and went to third when Tulowitzki fumbled Posey's potential double-play grounder.
Pence hit into a double play to score Belt and make it 1-all.
NOTES: Pence went 1 for 4 with an RBI and is hitting .318 with two home runs and 19 RBIs since the All-Star game. ... Hideo Nomo has the only no-hitter at Coors Field on Sept. 17, 1996, while with the Los Angeles Dodgers. ... Giants OF Andres Torres had surgery to remove bone spurs in his left Achilles. Carolina Panthers orthopedist Dr. Robert Anderson performed the surgery. Torres is expected to be sidelined for six months.