BALTIMORE -- The Colorado Rockies discovered why teams with power enjoy playing baseball at Camden Yards.
Colorado began Friday's series opener ranked third in the National League in homers, and the Rockies' flexed their power in a 6-3 win. They banged out four homers in the final four innings with Wilin Rosario's two-run shot giving the Rockies the lead for good over the Orioles.
While Rosario's home run proved to be the deciding blow, Colorado (58-65) also got solo homers from Charlie Culberson (in the seventh), Charlie Blackmon (eighth) and Todd Helton (ninth) as the Rockies scored runs in the last five innings.
"It's pretty cozy," Rockies manager Walt Weiss said of Camden Yards. "It's a cozy park, but you've still got to hit it, and we put some good swings on it."
Those good swings helped the Rockies rally after a tough start. Baltimore took an early 2-0 lead; Colorado had just one hit through the first five innings.
Orioles starter Wei-Yin Chen (6-6) shut down the Rockies -- for a while. Then the Rockies scored six consecutive runs and pushed the Orioles (65-56) to their fourth straight loss.
"I think Chen threw really well, and it took us a little while to solve him," Blackmon said. "We had some big hits."
Chen still was cruising even after Nolan Arenado's fifth-inning single cut the Orioles' lead to 2-1.
Despite giving up Culberson's first major league home run in the sixth inning to tie the game, Chen seemed to be in control.
It was the seventh inning when the wheels started to come off and the Rockies landed a staggering blow to the Chen and the Orioles.
Chen walked Michael Cuddyer and Rosario sent a fly ball to right that just made it onto a ledge near the foul pole for a two-run homer and a 4-2 Rockies lead.
"I thought it was a double," said Rosario, who's battling problems with both legs. "When the umpire let me know, I (was) happy. I mean I know they say the outfield is good for the hitters, now I know that it's good."
Blackmon replaced Culberson in left field in the seventh, and he belted a solo homer in his first at-bat in the eighth off Francisco Rodriguez.
Rodriguez left one batter later with a right groin strain.
Helton added the last homer off struggling Orioles closer Jim Johnson in the ninth. That was Helton's 362nd career homer, passing Joe DiMaggio for 76th on the all-time home run list.
Colorado starter Juan Nicasio (7-6) had control problems at times, walking four while striking out two in his six-inning stint, but the right-hander ended his two-game losing streak. He gave up two runs on four hits.
Josh Outman, Matt Belisle and Rex Brothers combined for the final three innings to give the Rockies their sixth win in seven games.
The Orioles' only hit after the third inning was a Matt Wieters homer off Brothers in the ninth.
The Orioles quickly jumped in front early when Nate McLouth led off the first inning with a solo home run to right on Nicasio's third pitch. McLouth crushed a 1-1 fastball for his eighth home run this season.
Baltimore added another run in the third when Adam Jones singled with the bases loaded for a 2-0 lead. But Nicasio then retired Nick Markakis and Wieters
NOTES: The Orioles announced that pitching coach Rick Adair took a leave of absence for personal reasons. No timetable was given for his return, and bullpen coach Bill Castro will take over Adair's job. Scott McGregor, one of the best pitchers in franchise history, will become the bullpen coach during this time. ... McLouth's lead-off homer in the first was his second lead-off homer this season. It also snapped a recent 0-for-8 slide. ... Rosario's fifth-inning double stretched his hitting streak to eight games. ... This is the first time the Rockies have come to Baltimore since 2007, when Colorado took two of three from the Orioles. That was the last time these two teams met before this series.