By NICOLINO DIBENEDETTO
(AP) -- The Washington Nationals may be one of the biggest surprises in baseball, but Jason Hammel's rise with the Baltimore Orioles may be just as stunning.
With their offense scuffling, the Orioles likely will need another strong effort from the right-hander Friday night when they face the Nationals in the opener of this three-game Beltway Series.
Washington (40-27) is the surprise leader in the NL East, as it tries to eventually reach the playoffs for just the second time in franchise history and first since 1981 as the Montreal Expos.
While the Nationals' success has been unexpected, the same could be said for Hammel (7-2, 2.87 ERA) after he was acquired by Baltimore (39-30) in a three-player trade with Colorado in the offseason.
He's among the AL leaders in ERA and has already matched his win total from last season.
Hammel had the best performance of his career in Saturday's 5-0 win at Atlanta. He carried a no-hitter into the seventh inning and finished with a one-hitter and eight strikeouts in his second career complete game and first shutout in seven major league seasons.
"It used to be, for me, too many things were going on," Hammel told the team's official website. "I was worried about the what ifs and what might happen instead of going hitter to hitter and that's what I was able to do. It's not rocket science."
Hammel is 4-0 with a 3.99 ERA in six starts against the Nationals, allowing four runs over 5 1-3 innings of a 6-5 victory May 19.
He may need to be better than that since the Orioles are hitting .159 with one homer and 12 runs during a 2-4 stretch. They're 0 for 17 with runners in scoring position in four games since Hammel's last start.
Baltimore batted .130 while being swept in a three-game series by the New York Mets, losing the finale 4-3 Wednesday after getting blanked in the first two contests.
"I know our guys are frustrated," manager Buck Showalter said. "We've beaten some very good pitchers and to get where we want to go, we're going to (have to find a way to keep doing that)."
The Orioles will be in for another test against the Nationals and their major league-leading 3.00 ERA.
Jordan Zimmermann (3-5, 2.92) has been a big part of Washington's strong staff but he's 0-1 in his past four starts. The right-hander has a 1.62 ERA in five road interleague outings, but just an 0-2 record to show for it since he's been backed by an average of 2.16 runs. That includes a loss in his only visit to Baltimore on May 22, 2011, when he yielded two runs and four hits in 6 1-3 innings of a 2-1 defeat.
Zimmermann allowed three runs - two earned - and five hits with six strikeouts in six innings, while his teammates committed two errors and provided two runs of support in a 5-3, 14-inning loss to the New York Yankees on Saturday.
The Nationals are trying to build on Thursday's 5-2 win over Tampa Bay, taking two of three from the Rays to improve to 9-6 in interleague play this season.
Bryce Harper was 4 for 12 with two RBIs against the Orioles in May, but is 5 for 28 in the past seven games overall.
Updated June 22, 2012