BALTIMORE (AP) -- A year ago, the Orioles bullpen readily gave up leads and their batters failed in clutch situations. This year's team is showing more poise and more power.
Nick Markakis homered and drove in three runs, Brian Burres pitched four-hit ball into the seventh inning and Baltimore held on to beat the Washington Nationals 6-5 Saturday night for their fourth straight victory.
To secure their seventh victory in eight games, the Orioles used three pitchers to get through the Nationals' three-run eighth inning that pulled their interleague rivals within a run.
"You're not going to win by three or four runs every night," Markakis said. "We're doing a good job under pressure."
The Nationals made it 6-4 in the eighth on Boone's two-run, bases-loaded single off Dennis Sarfate. Jim Johnson relieved and walked Wil Nieves to load the bases before hitting Lastings Milledge on the left shoulder to force in a run. Johnson then struck out Austin Kearns on a 3-2 fastball to end the threat.
"We gave ourselves an opportunity. We crawled our way back into it," Nationals first baseman Aaron Boone said. "We just couldn't finish it off tonight."
Washington struggled early against Burres (4-4), who allowed two runs, walked two and struck out three in 6 2/3 innings as the Orioles won for the seventh time in eight games. The left-hander had lost three consecutive decisions following a 3-1 start.
He had an early 4-1 lead thanks to Markakis' run-scoring single in the first and two-run homer in a three-run third. Twenty-two of the Orioles' first 32 homers were solo shots; the last nine have come with runners on base.
"Our pitching's been phenomenal, keeping us in games," said Baltimore's Jay Payton, who added another two-run shot. "We've been able to get some timely hits. Nobody in here's panicking. We come in here confident in ourselves. We know if we play good baseball, we've got a chance to win."
A triumph in the finale of the three-game series Sunday would match Baltimore's longest winning streak of the season and give the Orioles their first sweep of the Nationals.
"There's always room for improvement, but the way the guys play and the way they compete and the way they keep their poise, I think is as good as you're going to see," Baltimore manager Dave Trembley said.
Ryan Zimmerman hit a home run and Boone had two RBIs for Washington, which has dropped three of five games.
Melvin Mora doubled off the left-field wall with one down and Markakis' RBI single up the middle put the Orioles ahead 1-0 in the first. Washington tied it in the second when Dmitri Young singled, Boone doubled to left-center and Jesus Flores hit a run-scoring groundout.
Baltimore went up 4-1 in the third. Brian Roberts led off with a double, stole third and scored on Mora's single to left before Markakis hit Odalis Perez's first pitch over the right-center wall for his eighth homer.
Zimmerman's solo homer off Burres, a liner to left in the fourth, made it 4-2.
Payton's two-out, two-run shot gave the Orioles a 6-2 lead in the fifth. After Kevin Millar singled off third baseman Zimmerman's glove, Payton hit a 3-1 pitch into the left-field seats.
Perez (1-4) departed after yielding a season-high six runs on 10 hits, walking two and striking out two in five innings.
"It was bad," he said. "I couldn't keep the game on the line. It was one of those games where you believe before the game warming up that it will be one of the best games. By the time, the game starts, everything is different. It was like they knew what was coming."
Flores, the Nationals' catcher, was ejected for arguing balls and strikes in the top of the sixth by home plate umpire Tim McClelland.
Nationals RHP Shawn Hill, Friday night's loser, had a cortisone shot in his right elbow on Saturday and hopes to make his next scheduled start against Philadelphia on Wednesday. "It was just bothering me too much. ... (Friday) was brutal," Hill said. "Maybe this shot is enough to get me over the hump." ... Burres has allowed three or fewer earned runs in six of eight starts. ... The Orioles are 11-5 in one-run games. ... Perez lost for the first time in four career starts against the Orioles.