WASHINGTON -- Jordan Zimmermann shut down the highest-scoring team in the majors. Bryce Harper gave him all the support he needed.

Zimmermann blanked the Blue Jays for eight innings, Harper hit a go-ahead single off R.A. Dickey and the Washington Nationals ended a three-game losing streak by beating Toronto 2-0 Tuesday in the opener of a day-night doubleheader.

Zimmermann (5-2) threw a season-high 105 pitches and helped save a struggling bullpen.

"He was in command from the first pitch, throwing it where he wanted to," Nationals manager Matt Willams said. "Early on, he was keeping his pitch count down, which allowed him to go deep."

Harper singled during a two-run fifth against Dickey (2-6).

A day after rain postponed the first meeting between the teams since 2012, the game began with only a few dozen fans in the stands.

Zimmermann (5-2) gave up six hits, struck out four and walked one to win for the third time in four starts. After Toronto loaded the bases with one out in the seventh, Zimmermann got Russell Martin to ground into a double play.

Rather than go for his first complete game since throwing a no-hitter last year on the final day of the regular season, Zimmermann deferred to Washington's closer. Drew Storen pitched a perfect ninth, earning his 17th save in 18 chances for the NL East leaders.

"There was no discussion," Zimmermann said about returning for the ninth. "That was Drew's job. He can have it."

Harper's single gave him 29 RBI in his last 27 games. Ryan Zimmerman added a sacrifice fly later in the inning.

Dickey (2-6) gave up eight hits, struck out six and walked one in six innings.

Over his previous four starts, Dickey went 1-2 with a 7.92 ERA. Yet he pitched to Harper in the fifth with other numbers in mind.

The veteran knuckleball pitcher easily retired Harper in his first two at-bats, including a strike out looking in the first. That dropped the slugger to 3 for 16 in his career against Dickey. With that success rate, Dickey passed on intentionally walking Harper with runners at second and third base and one out in the fifth.

"I was committed to throwing good knuckleballs in the strike zone to him," Dickey said. "I was not afraid of facing him right there. ... If I have a good knuckleball, I don't care."

Despite his disdain for facing knuckleballs, Harper knocked a single up the middle to score Zimmermann, who opened the inning with a base hit.

"Maybe some other guys do, but I hate it," Harper said. "My numbers against Dickey are probably awful. I was just going in there, trying to battle as best I can. Luckily came up with a big knock right there to get a run on the board."

Max Scherzer was to start the night game for the Nationals against Marco Estrada for the Blue Jays.

TRAINER'S ROOM

Blue Jays: OF Jose Bautista made his first appearance in right field since straining a shoulder on April 21. ... In between games, Toronto activated C Dioner Navarro (hamstring) from the 15-day disabled list and sent C Josh Thole to Triple-A Buffalo.

Nationals: CF Denard Span did not play after leaving Sunday's loss at Cincinnati with a sore right knee. ... RHP Doug Fister (forearm tightness) threw approximately 20 pitches off a mound Monday without discomfort. Fister was placed on the 15-day DL on May 15.

IN THE GROOVE

Zimmermann has not lost since falling to 1-2 on April 18. Over his last four starts, he is 3-0 with 0.96 ERA in 28 innings. "I was a little off in the beginning, but everything is working now and right where I want t be," he said.

NEW ADDITIONS

Washington recalled OF Matt den Dekker from Triple-A Syracuse to serve as the 26th man for the second game of the doubleheader. Toronto brought up RHP Scott Copeland from Buffalo.

UP NEXT

Blue Jays: LHP Mark Buehrle (6-4, 4.97) is scheduled to start for Wednesday's series finale.

Nationals: With Stephen Strasburg on the DL, Williams hinted RHP Taylor Jordan (0-1) could start Wednesday.