WASHINGTON (AP) -- Dan Haren has shown no signs of turning around a season-long slump.
The right-hander allowed six runs over 3 1-3 innings with seven hits including his 19th home run surrendered and an RBI single to opposing starter Jhoulys Chacin, who pitched seven shutout innings as the Washington Nationals fell to the Colorado Rockies 7-1 on Saturday afternoon.
"Same thing that's gone wrong the last few weeks," Haren (4-9) said after losing his sixth straight decision, which snapped Washington's three-game winning streak. "Inability to get the ball down, putting us in a hole. It's the same story."
On Saturday, the three-time All-Star had two wild pitches and hit a batter while raising his ERA to 6.15. Over his last seven starts, he has allowed 11 home runs.
"I'm a little concerned about him," Nationals manager Davey Johnson said. "When he pitches up, he's in trouble," Johnson said. "I'm going to have a talk with him the next time he throws and see if we can't do something to make things better for him."
Asked if it's becoming difficult to watch his teammate go through his struggles, first baseman Adam LaRoche said, "A little bit."
DJ LeMahieu hit his first home run and Michael Cuddyer's RBI single in the first extended his hitting streak to 20 games, the longest active streak in the majors and tied for the longest this season.
Chacin (6-3) held Washington to five hits with one walk and three strikeouts and won for the third straight start.
Nolan Arenando added the seventh run with a solo homer off Ross Ohlendorf in the eighth as the Rockies snapped their season-high five-game losing skid. Ohlendorf allowed one run in 4 2-3 innings of relief.
Making his major league debut, Dickerson doubled in his first two at-bats and drove in a run during the Rockies three-run first inning off Haren.
"I got a hit, too, but we started really good with three runs in the first so that gave me some support where I could go out and just throw strikes and get outs and throw a lot of innings," Chacin said.
Ryan Zimmerman's home run with one out in the ninth off Wilton Lopez helped Washington avoid being shut out for the ninth time this season.
After Cuddyer's RBI single scored Carlos Gonzalez, Dickerson, called up from Triple-A Colorado Springs on Friday, doubled with two outs. That scored Cuddyer and staked Chacin to an early 3-0 lead.
After tossing consecutive 1-2-3 innings, Haren came apart in the fourth. Facing five batters before being yanked, he allowed three hits, including Chacin's RBI single, threw a wild pitch and plunked Josh Rutledge, who later scored on LeMahieu's RBI single to make it 6-0.
Replaced following Chacin's hit, Haren walked to the dugout amid a torrent of boos from the crowd of 35,787.
"No one wants to be booed," said Haren, whose last win came on May 9 against Detroit. "I'd probably boo myself too."
Depending on Johnson's course of action, which could include yanking the 32-year-old from the rotation, booing could be the least of Haren's problems.
"I'd be lying if I said I hadn't thought about it," Haren said. "It's a performance-based business and obviously I'm not getting the job done."
Notes: OF Jayson Werth was scratched from the Nats' lineup due to flu-like symptoms, Johnson said. Steve Lombardozzi replaced Werth in the lineup while Roger Bernadina shifted from left field to Werth's right field position. ... Nationals OF Bryce Harper, who has been sidelined since May 26 with left knee bursitis, is not convinced he can begin a rehab assignment as quickly as his manager believes. Davey Johnson had said Friday that he expects Harper to start a rehab stint Tuesday at Class A Potomac, but Harper said on Saturday he thought he needed an extra day or two. ... Colorado LHP Jorge De La Rosa (7-4, 3.21 ERA) faces LHP Ross Detwiler (2-5, 3.34) in Sunday's series finale.
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