WASHINGTON -- Left-hander Ross Detwiler showed once again that he wants to be in the big league rotation next year, guiding the Nationals to a 4-1 win over the D-backs on Monday night at Nationals Park.
Detwiler lasted 6 2/3 innings and allowed one run, which was scored in the seventh inning when Henry Blanco hit a home run over the left-field wall. Detwiler struck out three to earn his first victory since July 5.
"I don't want to discredit what the kid's doing," said D-backs manager Kirk Gibson. "He threw a good game. He came after us, but we couldn't put anything together. He didn't give us any free chances."
At one point during the game, Detwiler retired 15 out of 16 batters he faced. Detwiler said he credits his recent success to watching teammate Chien-Ming Wang, who, like Detwiler, relies heavily on a sinker.
"I get to watch him on TV, while I'm charting the game," Detwiler said. "It's huge for me to be able to see that and see him work [with the sinker] -- the conviction that he has with every sinker that he throws. It's funny going out there because every hitter knows what's coming, but he still gets ground-ball outs."
Besides the home run, the only other time Detwiler was in trouble was the sixth inning. He allowed two hits a walk and had the bases loaded, which tested manager Davey Johnson's patience.
"I'm going to see what he is made of right here," Johnson said. "This is the only jam he was in. I want to see him get out of it."
Detwiler got Paul Goldschmidt to ground into a force play at second base to end the threat.
"That was the crunch time for me. I was going to take one hitter at a time," Johnson said. "Tonight was outstanding. When we scored the three runs, I wanted to see him go out and go right after [the hitter]. He was a little tentative, but he recovered and pitched well. He had a really good fastball. He was spotting it. He has a little sinker with it, too. That was impressive."
Detwiler got some run support early as the Nationals struck off D-backs left-hander Joe Saunders -- and Jayson Werth had a hand in all four runs. The right fielder led off the second inning with a double and scored on a single by Jonny Gomes.
Two innings later, Werth hit his 15th home run of the year, a three-run shot over the right-field wall to give the Nationals a 4-0 lead.
As Werth reached the dugout, Johnson joked, "You can hit left-handers." Entering Monday's action, Werth was hitting .185 against southpaws.
Johnson believed Werth would have a solid game after watching him take batting practice.
"I think it's more getting comfortable here," Johnson said. "He's concentrating on the things he can do. Everyone, offensively, is starting to come around. Everybody has been kind of sleeping and kind of feeling their way. He has been no different other than my three [Ryan Zimmerman] and four [Michael Morse] hitters, who have been consistent."
Werth raised his batting average to .229 and is starting to feel comfortable at the plate. It helps that he is having success hitting the ball to right field for power. He declined to say how he was able to fix his problems at the plate.
"I should do that more often. It's a great ballpark to hit in," Werth said. "That right-center gap is closer than it looks. I'll take advantage a little bit more. I'll just keep working the right way. We still have a lot of baseball left. Hopefully, it will be all right.
"Probably the last week to 10 days, I've really locked it in. It was a struggle, really. It has been a long time coming. I knew where it was. I just didn't know how to get there. Finally, I feel I'm getting there."
After Detwiler left the game, Henry Rodriguez, Ryan Mattheus and Drew Storen blanked the D-Backs the rest of the way, with Storen picking up his 34th save. The Nationals (62-64) have won four of their past five ballgames and are 5-2 on the current homestand.
"We have a good ballclub. The future is bright," Werth said. "We have a lot of good players here. We are doing well."
Bill Ladson is a reporter for MLB.com and writes an MLBlog, All Nats All the time He also could be found on Twitter @WashingNats. This story was not subject to the approval of Major League Baseball or its clubs.