Closer Matt Capps came in during the ninth inning and allowed two runs, but managed to pop up Jason Kendall with runners on first and second to end the game.
"It was a good team effort," Nationals manager Jim Riggleman said. "It got a little hairy there at the end, but we'll take that."
Prior to Tuesday's matchup against the Royals, Atilano had lost three consecutive starts. But by getting ahead in the count early on and utilizing his four-seam fastball, he was able to effectively pitch against the Royals batters.
"He needs to get ahead in the count, and today he did," Ivan Rodriguez said of Atilano. "He was pounding the strike zone, had a good sinker, a good comeback sinker to right-handers on the outside part of the plate and a good slider. He did tremendous today."
During the rain delay, Atilano went and relaxed in the clubhouse. When it appeared the game would be restarted, he threw warm-up pitches to keep his arm loose. Riggleman said the extra throwing was a reason why Atilano finished after only 5 1/3 innings and 84 pitches.
Atilano said he felt he could have gone longer after the rain delay, but overall was happy with his performance.
"I've been working with [Nationals pitching coach Steve] McCatty in-between the starts and finally the work we put in together reflected in the games," Atilano said.
Washington's offense had struggled of late and provided very little run support for its starting pitchers. The Nationals had not scored more than three runs in a game since June 15 in Cleveland.
But Tuesday was a different story, as they put up four runs on 11 hits.
The middle of the lineup was particularly effective. Ryan Zimmerman, Adam Dunn and Josh Willingham combined for six hits -- two home runs -- and three RBIs.
"Zim swung the bat well and had a big RBI there for us," Riggleman said. "Willingham of course had a big night and Adam did what he can do. A lot of good at-bats."
The Nationals scored first in the third inning. With two outs and Cristian Guzman on first base, Zimmerman hit an RBI double off right-hander Anthony Lerew (0-1) down the left-field line to put Washington up, 1-0.
In the fourth inning, Willingham hit his 100th career home run off Lerew to left field to give the Nationals a two-run advantage.
Willingham said hitting home run No. 100 was a special moment for him.
"When I hit it, I knew I had a good chance," Willingham said. "It means a lot, and I'm sure it will mean more when I look back on my career and am done playing. You never set a goal to hit a number of home runs, but when you get to 100 or a number like that, it's pretty cool."
Later in the inning with the bases loaded and two outs, Nyjer Morgan's RBI sacrifice fly to center field put the Nationals up 3-0.
Dunn added a solo home run off Lerew in the fifth inning to center field to give Washington a 4-1 lead.
"Dunn's gonna hit homers," Royals manager Ned Yost said. "It wasn't actually a bad pitch. It was kind of a pitch that Adam Dunn gets extended on and hits a long way, which we all witnessed. But Lerew did a nice job, kept us in the game, gave us a chance."
Though down early, the Royals made it interesting in the late innings.
Right-hander Drew Storen entered the game in the seventh inning and did not allow any batter to reach base. But after Storen gave up a leadoff double to Chris Getz in the eighth and walked Scott Podsednik, Riggleman sent in right-hander Tyler Clippard.
With two men on and no outs, Clippard retired all three batters he faced.
Riggleman said he didn't want to use Clippard, but based on how Storen was throwing he had no other option.
"I was hoping to not use Clippard tonight," Riggleman said. "If I had finished out two with Storen, then I would not use him tomorrow. That was the plan. It just didn't happen."
Capps came in to close the game in the ninth, but quickly got into trouble.
After getting Jose Guillen to fly out to left field, Capps gave up three consecutive singles to load the bases. Following a popout by Getz to shortstop Ian Desmond, Podsednik hit a two-run single to right field to make the score 4-3.
But with runners on first and second, Capps managed to get Kendall to popout to Adam Kennedy at first base and end the game.
"We just battled through it and fortunately got the third out before they got their third run," Capps said. "The last few nights have been kind of a struggle to get through. Nonetheless, we got the 'W' and it makes it a little easier."
The Nationals have now won two games in a row and look to take the series against the Royals on Wednesday with rookie right-hander Stephen Strasburg to the mound.
"He's going to give us a great opportunity to win tomorrow, but if we don't score any runs for him, like his last start, its all for nothing," Dunn said. "Our goal as an offense is to put up some runs. He's going keep us in the game."