BALTIMORE -- After enduring two rain delays totaling nearly three hours, the last thing Ramon Hernandez wanted to do was put on his catcher's gear in the 10th inning.
So he made certain the game didn't get that far.
"It was a long day. It's good to come out on top," Orioles starter Adam Loewen said. "You lose, and it feels like a waste of time."
The end came close to six hours after the first pitch, and only five minutes after play resumed following a stoppage of 2 hours, 18 minutes.
The game was halted a second time with the Orioles ready to bat in the ninth.
When the tarp was finally removed, Chad Cordero (2-3) walked Luis Matos. After a sacrifice by Brian Roberts and an intentional walk to Melvin Mora, Miguel Tejada hit a fly ball to left. Hernandez then hit a liner between short and third, and Matos scored without a throw.
"Everybody was tired and stiff," said Hernandez, who also homered. "I know one thing: I didn't want to go back to catch. I got lucky, I hit it where nobody was playing."
By game's end, only a few hundred people were left from the crowd of 36,920.
Javy Lopez got three hits for Baltimore, including the 1,500th of his career. The milestone hit came in the eighth, the second straight inning in which the Orioles failed to score after loading the bases.
Todd Williams (2-3) pitched two scoreless innings for Baltimore.
Jose Vidro had two hits and scored a run for the Nationals, who got only one hit after the third inning and lost their fifth straight. Washington went 1-for-8 with runners in scoring position after going 0-for-8 Friday night in a 2-1 defeat.
"We're just not clicking right now," Nationals manager Frank Robinson said. "We're not clicking on any cylinders, and I really don't know why."
Robinson was miffed at Cordero for walking Matos, which set up the chain of events that led to yet another one-run loss -- the 12th this season for Washington.
"We've been talking about it all year. You dig a hole for yourself and you're going to get buried," Robinson said.
Rain interrupted play for 26 minutes in the top of the seventh after Orioles reliever Chris Britton walked Vidro and Royce Clayton with two outs. When play resumed, Kurt Birkins struck out Nick Johnson, back in the lineup after missing a week with a lower back strain.
In the bottom half, the Orioles loaded the bases with two outs against Jon Rauch before Tejada grounded out.
Baltimore filled the bases with one out in the eighth, but Jeff Conine hit into a double play.
Loewen needed 104 pitches to get through five innings. The rookie gave up two runs and four hits, walked six and struck out five.
It was Loewen's fifth start, the first in which he did not face a former Cy Young winner. In his previous outings, the left-hander went up against Randy Johnson, Tom Glavine and Roy Halladay - twice.
The opposing pitcher this time was Michael O'Connor, who gave up two runs and six hits in six innings.
"He was fine. It was a real good performance," Robinson said.
After Hernandez hit his 13th home run leading off the second inning, Washington went up 2-1 in the third. Clayton drove in a run with a groundout before Ryan Zimmerman ended an 0-for-16 run with a two-out RBI double. Jose Guillen then grounded out with runners on second and third.
The Orioles pulled even in the fifth when Conine singled, took third on a double by Matos and scored on a single by Roberts.
Hernandez's 13 homers are one more than he hit all last year with San Diego. ... O'Connor has only one win in his last nine starts despite posting a 3.81 ERA. ... Britton has allowed runs in only four of 22 outings. ... Zimmerman's third-inning double was his first hit since a walkoff homer on Sunday against the Yankees.