WASHINGTON - The defending National League East champion Washington Nationals keep finding ways to lose.

With a chance to close within a half-game of the front-running New York Mets on Sunday, the Nationals, who have lost seven of 10 games, couldn't hold a lead at home with All-Star right hander Max Scherzer on the mound. They fell 6-4 to lowly Colorado when usually sterling reliever Drew Storen allowed a single to Ben Paulsen, hit Michael McKenry who was trying to bunt, and then gave up D.J. LeMahieu's game-winning two-run single.

"I made good pitches and sometimes those ground balls find a hole," said Storen, who was demoted from closer to set-up man when the Nationals acquired Jonathan Papelbon from Philadelphia before last month's trade deadline.

"It's important for us to realize how important (Drew's) been for us and continue to show the confidence we have in him," said Nationals manager Matt Williams.

Although Storen had surrendered a game-winning grand slam to red-hot Carlos Gonzalez in the eighth on Friday, Rockies manager Walt Weiss said that he wasn't comfortable with the ex-closer coming into the game.

But Storen, who entered the series with a 1.52 earned run average, left it with a 2.70 ERA as Washington finished a 3-4 home stand heading into a nine-game trip to NL West leader Los Angeles, defending World Series champion San Francisco and Colorado.

"We're not sitting there watching the scoreboard in August," said Ryan Zimmerman, who homered twice for the Nationals (57-53). "We just gotta stay within striking distance and get where we need to be with two or three weeks left in the season."

Gonzalez, who's batting .394 with 15 homers and 34 RBIs in his last 27 games, hit solo shots off a curveball and an 0-2 fastball from Scherzer.

"He's a lot of fun to watch right now," LeMahieu said. "The ball is coming off his bat really well. I'm just glad he's on our team."

Light-hitting Daniel Descalso also went deep for the Rockies (47-62) on a Scherzer fastball down the middle.

"You can't ever afford to leave the ball in the middle of the plate and I paid for it," said Scherzer, who struck out 10 in six innings but remained at 11-8 despite a 2.44 ERA.

John Axford (4-5) got five outs for the win, and Tommy Kahnle worked out of a bases-loaded jam in the ninth while recording his second save.

The Rockies (47-62) took a 4-3 lead in the sixth when Descalso was intentionally walked with a runner on second. The strategy backfired when little-used rookie Kyle Parker ripped the next pitch to left for a run-scoring single.

"Max is facing a guy who doesn't have a whole lot of at-bats and (Descalso's) got a home run already so we're going to go with the (better) matchup," Williams explained.

The Nationals fought back to tie it at 4 in the bottom of the sixth when Jayson Werth scored on Michael Taylor's one-out bouncer to third. Nolan Arenado's throw home pulled McKenry away from the plate.

Zimmerman and Werth had connected on consecutive pitches in the second off Rockies starter Yohan Flande to give Washington back-to-back homers for the first time this year. Zimmerman's homer in the third was his ninth of the season and fourth in 42 at-bats since being activated from the disabled list following a foot injury.

MR. EXTRA BASE

Eight of Zimmerman's 13 hits since he returned from the DL have gone for extra bases (five doubles, three homers).

TRAINER'S ROOM

Rockies: With a day game after a night game in the midst of 10 straight games without an off day, manager Walt Weiss rested C Nick Hundley and LeMahieu in favour of McKenry and Descalso. LeMahieu entered in the seventh.

Nationals: RHP Aaron Barrett's option was voided. He was placed on the 15-day DL retroactive to Aug. 6 with a sprained right elbow.

UP NEXT

Rockies: RHP Jon Gray (0-0, 4.50 ERA) opens Colorado's four-game series in New York against the Mets on Monday night. Gray, 23, allowed five hits and two earned runs in four innings in his major league debut last Tuesday against Seattle.

Nationals: LHP Gio Gonzalez (8-4, 3.75 ERA) gets the ball for Washington on Monday night in the opener of a three-game series in Los Angeles against the NL West-leading Dodgers. Gonzalez is 2-0 with a 2.61 ERA in four starts since the All-Star break.