Jason Marquis rebounded from his shortest start of the season with a decent outing that wasn't enough. Colorado's Todd Helton drove in a pair of runs - one on a solo homer leading off the fourth - and the Rockies edged the Nationals 2-1 on Saturday night, Washington's third straight loss.
It's the sixth consecutive one-run game for the Nationals, who are 3-3 over that span. Washington fell a game under .500 at 43-44.
The Nationals didn't get a hit off Ubaldo Jimenez until the fifth inning - after the right-hander, who already has one no-hitter on his resume, retired the first 13 hitters he faced. MIchael Morse ended his pursuit of perfection with a single to right, and the following inning, Ian Desmond led off with a triple and scored on pinch hitter Rick Ankiel's groundout to cut the Rockies' 2-0 lead in half.
Marquis (7-4), who was pounded for seven runs (six earned) in his last outing against the Pirates on July 3, yielded two runs on five hits, walked four and struck out one in six innings. He's 0-2 in five starts since his last victory June 10.
Jimenez (4-8) went eight innings, allowing a run on five hits. He walked one and fanned eight. Huston Street worked the ninth for his 26th save in 28 tries.
Washington got the leadoff runner on in the ninth inning when Ryan Zimmerman was credited with an infield hit on a grounder to short that Troy Tulowitzki slipped on while planting his back foot to throw. After Laynce Nix struck out, Morse hit a single to left, sending Zimmerman to third. But Jayson Werth grounded into a 6-4-3 double play to end it.
The game drew a crowd of 29,441, a total that included 58 canine fans for "Bark in the Park Night."