WASHINGTON (AP) -- Charlie Blackmon had four hits and scored four runs and the Colorado Rockies roughed up Erick Fedde in his major league debut, beating the Washington Nationals 10-6 on Sunday in the opener of a day-night doubleheader.
Blackmon had four singles, while DJ LeMahieu had three hits, including two doubles, and scored twice. Nolan Arenado added three hits and two RBIs.
Fedde (0-1) allowed 10 hits and seven runs - five earned - in four innings while striking out three.
The 2014 first-round selection loaded the bases in the first inning before recording his first out on Gerardo Parra's double-play groundout that scored Blackmon. Ramiel Tapia's single scored LeMahieu one batter later and Colorado led 2-0 after the first inning.
Kyle Freeland (11-7) went five innings, allowing nine hits and four runs while striking out four.
Ryan Zimmerman hit two home runs and Wilmer Difo also homered for Washington. Both finished with three hits.
Fedde settled down in the second by striking out the side but struggled with the top of the Rockies' order in the third and fourth innings before exiting the game with the Nationals trailing 7-4. Colorado scored at least two runs in three of the four innings Fedde pitched.
Zimmerman had a three-run homer in the third inning and a solo shot in the seventh. He has 24 homers this season and his four RBIs left him tied for the most in franchise history with Tim Wallach, who played with the Montreal Expos from 1980-92.
Arenado tripled in Blackmon in the eighth while Ryan Hanigan had an RBI double in the ninth.
Greg Holland picked up his 33rd save.
Rockies: LHP Jake McGee (mid-back strain) was placed on the 10-day DL retroactive to July 27. "Jake's been feeling it for a few days. In St. Louis it started bothering him a little bit . when he was warming up yesterday he felt it again," said manager Bud Black. Colorado recalled LHP Zac Rosscup from Triple-A Albuquerque. He has allowed one run in 3 2/3 innings this season for the Rockies and Chicago Cubs.
Rockies: RHP Jon Gray (3-1, 5.84) is 1-1 with a 7.65 ERA in five starts on the road this season.
Nationals: RHP Edwin Jackson (1-1, 4.76) makes his second home start since returning to Washington. Jackson is 1-4 with a 10.80 ERA against the Rockies.