WASHINGTON -- Jason Hammel turned in his longest start of the season and Nick Markakis and Yamaico Navarro each drove in two runs as the Baltimore Orioles defeated the Washington Nationals 6-2 Monday.
Manny Machado added a double and two singles, Chris Davis had two hits and scored twice, and Adam Jones had a double and an RBI-single as the Orioles (28-23) piled up 15 hits in winning for the fifth time in seven games.
Hammel (7-2) pitched eight innings, allowing eight hits and two earned runs with eight strikeouts and no walks. He improved to 6-0 with a 3.16 ERA in eight career starts against Washington, including 4-0, 3.25 at Nationals Park.
Ryan Zimmerman had two hits and an RBI for the Nationals.
Washington's Gio Gonzalez (3-3), who fashioned a 1.29 ERA in his three previous starts, struggled with his control and it eventually caught up with him.
Davis walked to open the Orioles fourth and Matt Wieters singled. Steve Pearce flied to deep left and Davis tagged, just beating Tyler Moore's throw at third. On a 3-2 pitch, Navarro singled home Davis to tie the score 1-1.
After Hammel bunted the runners to second and third, Markakis hit the first pitch from Gonzalez for a two-run single, extending his hitting streak to 12 games.
In the fifth, Jones led off with double, went to third on a broken-bat single by Davis, and scored on a sacrifice fly by Wieters to make it 4-1.
Gonzalez, in his shortest outing since April 30, left with two outs in the sixth. He surrendered four earned runs on eight hits, while striking out three and walking four.
Washington (26-25), playing without Bryce Harper, got a run back in the sixth when Denard Span tripled and scored on Zimmerman's single.
Navarro, whose RBI in the fourth was his first in seven games as an Oriole, made it 5-2 in the seventh when he singled home Davis.
Jones closed out the scoring with an RBI-single in the eighth.
The Nationals broke on top when Adam LaRoche led off the second inning with a single, stole second and scored on Moore's double.
Washington went just 2-for-11 with runners in scoring position.
NOTES: An MRI revealed no structural damage to Harper's ailing left knee, but he was diagnosed with bursitis in the knee. Manager Davey Johnson said he could return as the DH Wednesday or Thursday at Camden Yards. Harper injured the knee May 13 when he ran into the wall in Los Angeles, and aggravated it Sunday when he slid head first twice and fouled a ball of it. Roger Bernadina started in RF. ... The Nationals placed Ross Detwiler (right back muscle strain) on the 15-Day DL retroactive to May 16 and recalled LH reliever Xavier Cedeno from Class AAA Syracuse. ... Machado leads the majors with 23 doubles. ... RHP Kevin Gausman (0-1, 7.20) starts for Baltimore Tuesday. Johnson has not yet named his starter.