PHOENIX -- Despite a late rally, the Nationals' eight-game winning streak came to a mostly sloppy end on Sunday at Chase Field.Washington made too many mistakes, couldn't get anything going against Arizona lefty Patrick Corbin and left an under-the-weather Ross Detwiler to battle through 4 2/3 innings, eventually falling in the series finale, 7-4. The Nats had not lost since the second half of their Aug. 3 doubleheader against the Marlins in Nationals Park, and they hadn't lost on the road since July 27 in Milwaukee. "As much as I wish, we weren't going to win every game the rest of the season," third baseman Ryan Zimmerman said. "We're going to lose, just like everyone else loses." The tone was set early, when Bryce Harper singled with one out in the first, collided with umpire Mike Muchlinski as he rounded the base and ended up getting picked off, slipping between first and second. Nationals manager Davey Johnson said Harper could have advanced to second, and they would have argued for umpire's interference, but the rookie hurried back to first. Harper's hit was the only damage dealt to Corbin through the first six innings, as the young lefty faced the minimum until the seventh. He ended up allowing two runs on four hits in seven innings. "I felt really good today coming in," Corbin said. "They are really aggressive, so if you fall behind, they are going to attack you and sit on a fastball. I mixed it up and got ahead of them to get some quick outs." Detwiler, meanwhile, gave up five runs (four earned) on three hits, a walk and two hit batters. Johnson said he could tell by Detwiler's mannerisms that he wasn't feeling right, adding that he was "all messed up" with sinus problems and had a hard time standing up on the mound after the fourth inning. But the manager praised Detwiler for battling as long as he did despite how he felt. Detwiler wasn't as complimentary of his own performance. Coming off two excellent starts where he used his power sinker to efficiently induce groundouts, he said he was leaving too many pitches up in the zone. Of the 14 outs Detwiler recorded, only three came via ground balls. "That's not an issue. I don't want to talk about that," Detwiler said when asked if how he felt affected his performance. "I just didn't get the ball down today. ... If I'm feeling bad and I still get my pitches down, then I get outs and it looks a whole lot better. I don't think that's the excuse why I did bad at all." The D-backs' first run wasn't the fault of Detwiler, though. In the second inning, Paul Goldschmidt hit a grounder at Zimmerman, whose throw missed Adam LaRoche at first base. Goldschmidt took second on the error, stole third and scored when catcher Kurt Suzuki's throw sailed into left field. "The errors just add to the misery," Johnson said. "But [Detwiler] battled them and hung tough." Detwiler gave up two more runs in the third. Goldschmidt once again did the damage for Arizona, knocking a two-run double to left field to make it 3-0. The D-backs began to pile it on with a four-run fifth inning. Detwiler snagged Jason Kubel's line drive for the second out, a ball that was on a collision course with his face, and his day was done. "It does take a toll on you and your body and makes you kind of feel foggy out there," Suzuki said. "It's tough going out there like that." But the damage was far from done, as Goldschmidt drove in another run with a single up the middle off reliever Craig Stammen. Justin Upton brought home Goldschmidt with a double to left field and scored on Miguel Montero's double to center. That put Arizona ahead, 7-0. But the Nats rallied back, even if it was too late. They broke through against Corbin with two runs in the seventh. Danny Espinosa doubled and scored on a single by Zimmerman. Pinch-runner Cesar Izturis went to third on a single by Michael Morse, who extended his hitting streak to 10 games and scored on a sacrifice fly by LaRoche. Morse's RBI double and Jayson Werth's run-scoring groundout in the ninth forced the D-backs to call closer J.J. Putz, but Roger Bernadina, representing the tying run, struck out to end the game. "There's no give-up on this ballclub. They're going to keep battling you," Johnson said. "They did very well, so they weren't planning on using their closer. Get him in, tying run there, anything can happen at that point." But the D-backs got out of it and left with a win. The Nationals, meanwhile, boarded their flight to San Francisco with a feeling they hadn't experienced in quite some time. "Anytime you lose, it stinks, no matter what," Suzuki said after his first loss in a Nationals uniform. "It was a little different."