Brian Matusz

Orioles training staff and teammates check on starting pitcher Brian Matusz during the sixth inning in Washington. (MCT photo / June 18, 2011)

There was no consistent or significant spike in Brian Matusz's velocity, but for five innings Saturday afternoon, the young left-hander made enough quality pitches to provide encouragement for a team desperately in need of it.

But any good sentiment was gone by the time Matusz limped off the mound in the sixth inning, two batters after Washington Nationals first baseman Michael Morse broke a tie by driving an 87 mph fastball into the home bullpen for a two-run home run.

Matusz, who needed help from one of the team's athletic trainers to get down the dugout steps, was diagnosed with left hamstring cramps and isn't expected to miss his next start. That was about the only good news for the Orioles, who fell, 4-2, in front of an announced 36,614 at Nationals Park and are a season-high six games under .500.

The Orioles (31-37) have lost six of their past seven games, are just 1-4 on this road trip and have dropped 10 of their past 12 contests away from Camden Yards.

"We don't live in that world," manager Buck Showalter said when asked how frustrating this road trip has been. "It's a realistic world. I don't think the road trip is over. We'll be here tomorrow. We don't live in that 'woe is me, the sky is falling' thing. You keep grinding. We had some good things happen and just haven't been consistent as a whole. We look at tomorrow as the start of that."

The Nationals (35-36), meanwhile, have won eight straight games, their longest streak since August 2009. They'll go for a three-game sweep Sunday afternoon with the Orioles badly in need of a strong outing from Chris Jakubauskas, a few clutch hits from an offense that appears allergic to them these days and one day without their losing a key performer.

Two innings before Matusz left the game, left fielder Luke Scott was removed because of recurring back spasms. Neither player expects to be sidelined for an extended stretch.

"I've had cramps before during a game where you'll feel a cramp in your hamstring [and] you're able to walk it off," said Matusz, who was removed from the game after first baseman Derrek Lee noticed him grimacing and summoned Showalter and the athletic training staff to the mound. "Today, I felt the cramp and my next pitch it was still locked up. I just didn't have everything behind it. It was just one of those things with the hot day and everything. We'll take care of it and move forward."

In getting his second loss in four starts since returning from the disabled list, where he spent two months because of a strained left intercostal muscle, Matusz (1-2) allowed four earned runs on six hits and three walks while striking out five over 5 1/3 innings.

Ryan Zimmerman launched a solo homer off him in the first inning, answering Adam Jones' homer in the top half off Washington starter Jordan Zimmermann (5-6). Zimmerman's double off the wall in the right field preceded Morse's two-run homer in the sixth, which broke a tie at 1.

It was Morse's 13th homer of the season, and it gave him a career-high 42 RBIs. Both his and Zimmerman's homers came on 87 mph fastballs. Matusz, whose velocity remains an issue, didn't hit 90 mph once on the stadium radar gun but did show far better command than he had in his previous three starts.

"It was a huge step forward from my last start," Matusz said. "That was pretty evident, but there's still a lot of room to go, still a lot of building, a lot more room for improvement. You want to go out there every day when you pitch and compete well enough to give your team a chance to win. Today, just not enough. But it was a lot better than my last outing, just be able to move forward and keep it going."

In his previous start, Matusz lasted just 1 1/3 innings, allowing four earned runs on five hits, four walks and four steals against the Tampa Bay Rays. His command and ability to hold base runners were questioned by Showalter. The manager was a little more optimistic about Matusz's latest start.

"It was somewhat better," Showalter said. "Hopefully, it's a step in the right direction."

Clay Rapada relieved Matusz in the sixth and gave up an RBI double to Ivan Rodriguez that extended Washington's lead to 4-1.

The Orioles, who managed just Jones' first-inning homer over the first six frames against Zimmermann, cut their deficit to 4-2 in the seventh on singles by Mark Reynolds, Nolan Reimold and J.J. Hardy. After Hardy's RBI single, Nationals manager Jim Riggleman took out Zimmermann and brought in hard-throwing Henry Rodriguez, who retired Nick Markakis and Jones to escape further damage.

Rodriguez got an inning-ending strikeout of Reynolds, who represented the tying run, in the eighth before Drew Storen pitched a perfect ninth to pick up his 17th save.

"We just have to be able to get the big hit," said Jones, whose team is 6-for-22 with runners in scoring position in the series and has stranded 20 base runners. "We have to be able to get the runner in. That's what it is. It's not a lack of base runners, it's not a lack of opportunities. It's just a lack of production. We've put ourselves in position the last five or six games, we just haven't gotten over that hurdle of getting that hit."

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