SAN FRANCISCO -- Rockies left-handed pitcher Jorge De La Rosa's early-season spiral pattern continued Friday night.
Just like his previous two starts, De La Rosa enjoyed all-too-brief dominance, followed by utter ineffectiveness, then exited after 4 1/3 innings. This time, De La Rosa coughed up a grand slam to opposing pitcher Madison Bumgarner in the Rockies' 6-5 loss to the Giants at AT&T Park.
After winning 16 games last year, De La Rosa (0-2) has a 9.69 ERA. His six strikeouts Friday gave him 16 in just 13 innings, but that's about the only good number that can be recited. Friday's struggles negated a majestic two-run homer from Carlos Gonzalez and three hits from Josh Rutledge, who started at shortstop while Troy Tulowitzki rested a tight right quadriceps.
The Rockies had a chance in the eighth, but some strong Giants defense and ill-fated baserunning made that chance go by the wayside.
Friday was similar to De La Rosa's last start, except for the fact the Rockies couldn't complete the comeback the way they did in beating the D-backs last Saturday. Then again, success is rare at AT&T Park, where the Rockies have won two of their last 17 games and six of their last 31.
The Rockies are willing to try to pick up De La Rosa until he can pitch like the guy who has two 16-win seasons in a Rockies uniform (2009, 2013).
"You can't just freak about it," Gonzalez said. "It's only been three games and he's not pitching the same way he was last year, but it's going to happen for him. Everybody's going to go through tough moments."
Gonzalez's fourth homer of the season, which landed in McCovey Cove beyond the right-field seating, came in the top of the third. It was the 29th so-called "splash hit" by an opposing player and just the second for a Rockies player. Gonzalez had the other one last May 29.
De La Rosa struck out four in the first two innings. The only baserunner was Hector Sanchez, who struck out but took first when the pitch bounced and catcher Jordan Pacheco bounced his throw to first base.
The Giants' Brandon Crawford tripled to open the third and Bumgarner nearly homered but ended up with a sacrifice fly to the left-field warning track.
But De La Rosa unraveled with two out and two on in the fourth. He hit Brandon Hicks, then walked Crawford to force in a run. This time, Bumgarner hit De La Rosa's fastball just a little harder, and it ended up in the left-field seats. De La Rosa gave up six runs on four hits, two walks and the hit batsman.
"Bumgarner, you have to treat him like he's another hitter," Gonzalez said. "Over the years, he's proven that he can handle the bat. He hit the ball hard. First at-bat he hit the ball hard. He saw a cookie with the bases loaded and took advantage of it."
Rockies manager Walt Weiss still trusts that De La Rosa will demonstrate why he was the Rockies' Opening Day starter.
"Command got away from him, it looked like," Weiss said. "He got some balls up and out over the plate.
"He's got a good track record. I put a lot of stock in that. He was good early, looked like he had his 'A' game early, then it got away from him."
Or maybe Bumgarner took it away from him. Bumgarner's slam, which gave the Giants a 6-3 lead, was just the second by a pitcher since the team moved from New York to San Francisco in 1958. Shawn Estes had the other on May 24, 2000.
"I'm just thankful to run into something and score some runs for us," Bumgarner said. "It's a good ballclub they got, all the talent they got. They've really got some good hitters in there and good pitching."
The Rockies' Charlie Culberson doubled in a run in the sixth off Bumgarner (2-0), who gave up nine hits and four runs in six innings. Bumgarner escaped a two-on, no-out jam in the fifth and stranded Culberson in the sixth by striking out Brandon Barnes to end the frame.
In the Rockies' eighth, Nolan Arenado led off with the first bunt single of his career against Santiago Casilla, took second on third baseman Pablo Sandoval's throwing error and scored on pinch-hitter Charlie Blackmon's single. Blackmon went to second on the throw home.
A leaping Casilla snatched Pacheco's one-hopper and threw to second, where Crawford made a spinning tag to erase Blackmon.
"That's a situation where zero times out of 100 I should go until that ball gets by him," Blackmon said. "He made a good play. But he should have only gotten the out at first. I thought the ball was going to get by [Casilla]. I think that's a mental mistake on my part."
Pacheco reached base, but dashed for second on DJ LeMahieu's line drive to center and easily was doubled off by Juan Perez's throw.
"When you're running [on a] 3-2 [count], he's got to pick up the ball," Weiss said.
Giants closer Sergio Romo earned his third save with three ninth-inning looking strikeouts. The Rockies were incredulous over plate umpire Dan Iassonga's third-strike calls to pinch-hitters Justin Morneau and Tulowitzki.