A victory over their neighboring rivals made the detour much more tolerable.
Nick Markakis homered for the Orioles, who trailed 3-1 before rallying for their eighth win in 11 games.
The game was a makeup of the July 8 contest that was postponed by rain. A sellout crowd of 42,181 -- many of them wearing Oriole orange -- showed up to watch teams located just 38 miles apart on I-295.
The Orioles wanted the makeup game to be played in the afternoon, but the Nationals nixed the request. So Baltimore planned on taking a red-eye to Toronto for a three-game showdown between the top two teams in the AL East.
"It was a tough one, and then again tomorrow and the next day," manager Buck Showalter said. "These guys get to sleep around 5 or 6. It's part of what we have to go through to get what we're trying to get done."
Hardy and Ryan Flaherty opened the seventh with successive doubles off Tanner Roark (11-7) to tie it at 3. Delmon Young followed with an RBI single -- making him 9 for 17 as a pinch-hitter this season -- and Adam Jones capped the uprising with a run-scoring single, Baltimore's sixth hit of the inning.
Young has been a significant contributor in his first season with the Orioles, whether starting or coming off the bench.
"He got a big hit," Showalter said. "He works so hard at it. I see him rattling in the cage from the first or second inning on."
Joseph singled in two runs in the eighth to make it 7-3.
Kevin Gausman (6-3) gave up three runs and eight hits in six innings for the Orioles.
"I definitely had to grind through that one," he said. "I think it was kind of huge to get through six there."
Washington's lead over Atlanta in the NL East slipped to three games and Baltimore increased its margin over Toronto to four games.
Roark allowed five runs, the most he yielded in 16 starts since May 3. He won his previous four starts, allowing only one run in each game.
"The ball was up, elevated, I wasn't hitting my spots," he said. "If the ball's up and I'm not hitting spots, I'm going to get hit hard."
He gave up seven hits, including two homers. Roark hadn't allowed more than one home run in a game since that May 3 game against the Phillies.
"They're in first place for a reason," he said of the Orioles. "They hit the ball, and they showed it tonight."
Wilson Ramos put the Nationals up 1-0 in the second inning with his first home run since July 9, against the Orioles.
Joseph homered in the third, the first run against Washington in 23 innings. In the bottom half, Jayson Werth hit a sacrifice fly after a double by Denard Span, who has reached via a hit or walk in 30 straight games.
Markakis made it 3-2 in the fifth with his 10th home run, matching his total of last season.
Orioles: Right-hander Ubaldo Jimenez (right ankle sprain) has completed his rehabilitative work in the minors and could be activated from the DL as soon as Friday.
Orioles: Baltimore will start right-hander Bud Norris on Tuesday night in Toronto. He's 2-0 with a 1.83 ERA against Toronto this season.
Released by Oakland over the weekend, former Orioles right-hander Jim Johnson worked out for Baltimore at the team's training complex in Florida.
If signed by the Orioles, Johnson would likely receive a minor league deal.
"He's certainly got a good pedigree and history of having success," Showalter said. "He's got himself a tough decision to make, but a good one. He's got some people interested in him."