MLB: Colorado 4, Washington 1

WASHINGTON, Aug. 20 (UPI) -- Jason Hammel allowed three hits over seven innings Thursday and the Colorado Rockies improved their wild-card position by fighting off Washington 4-1.

The Rockies won their fourth in a row and boosted their lead in the National League wild-card race to 2 ½ games over San Francisco. Colorado also began the day just three games behind the Los Angeles Dodgers in the National League West.

Hammel (8-7) gave up Washington's only run in the sixth and walked just two. He had lost four of his previous six decisions.

Colorado took a 2-0 lead in the fifth when Carlos Gonzalez delivered an RBI double and Yorvit Torrealba scored on a wild pitch.

The Rockies were protecting a 2-1 lead in the eighth before Troy Tulowitzki doubled home Todd Helton and then scored on a single by Brad Hawpe. Huston Street worked a perfect ninth for his 32nd save.

The loss went to Garrett Mock (2-5), who gave up just three hits and struck out eight over five innings. Mock, however, left the game with the Nationals trailing by a run.

It was Washington's third straight loss. The Nationals are on pace to lose 104 games this season.