TORONTO -- Stepping into the box for his second at-bat, Bryce Harper was determined to swing at the first pitch. He did, and connected on the longest home run of his brief career.
Harper homered off the restaurant in center field, Danny Espinosa added a two-run blast and the Washington Nationals beat the Toronto Blue Jays 4-2 on Tuesday night, extending their winning streak to five games.
"I don't really hit big home runs," Harper said. "It's usually just line drives that get going. That was a pretty good one tonight."
Jhonatan Solano added his first career homer as the Nationals improved to 6-2 in interleague play.
(Wednesday) is going to be a big day," manager Davey Johnson said. "We've got our big horse going. We just need to finish this off."
Washington's five-game winning streak matches a season best. The Nationals also won five straight from April 10-14.
The win, coupled with Atlanta's home loss to the New York Yankees, gives Washington a four-game lead atop the NL East.
Jose Bautista hit a two-run shot, but the Blue Jays lost for the fifth time in six games and dropped to .500 at 31-31. Toronto has not been below .500 at any point this season.
Harper posted his second straight three-hit game, finishing 3 for 4. He singled in the first, homered in the third, grounded into a fielder's choice in the fifth and reached on a bunt single in the eighth. Harper has reached safely in eight of his past 10 plate appearances.
"He's hitting about everything they throw up there," Johnson said.
Harper said he feels good at the plate, but suggested there's still room for improvement.
"At the beginning of the year, I usually struggle and then once I get going, it's scary," he said. "I've always said that."
Chien-Ming Wang earned his first victory as a starter this season in his third attempt, allowing two runs and four hits in five innings. Wang (2-2) walked five and struck out five.
The Nationals opened the scoring in the third when Harper blasted his seventh homer, a two-out shot that smacked off the windows of the restaurant in center. The impressive drive left many in the crowd of 22,538 gasping at the teenage rookie's raw power.
"That was a changeup right in his wheel house and he didn't miss it," Johnson said. "I don't know why the outfielder went back. It was obviously a long way out of here."
Harper said he had made up his mind to take a healthy cut even before he stepped into the box.
"I was going up there swinging out of my shoes first pitch," Harper said. "I already made my mind up in the on-deck circle. I didn't care if it was a curveball (that went) 54 feet."
The Blue Jays used a hit batter, a single and a walk to load the bases with two outs in the bottom half, but Wang caught Edwin Encarnacion looking to end the threat.
"We're scuffling right now a little bit with men in scoring position," manager John Farrell said.
Washington got another two-out homer in the fourth, with Espinosa hitting a two-run shot to center, his sixth.
Bautista brought the Blue Jays to within one in the fifth with a two-run shot to left, his 18th. Bautista has homered three times in his past five games.
Solano made it 4-2 with a two-out solo homer to left in the seventh on a 0-2 pitch.
All three Nationals homers came off Blue Jays right-hander Henderson Alvarez, extending his winless streak to six starts. Alvarez (3-6) allowed four runs and nine hits in seven innings. He walked none and struck out three.
Alvarez, whose last victory came May 10 at Minnesota, is 0-4 with a 5.50 ERA in his six starts since, all losses.
"When he's missed on the plate, he hasn't gotten away with a mistake," Farrell said.
Tests on Toronto RHP Brandon Morrow, who left Monday's start after just nine pitches, confirmed the initial diagnosis of a strained left oblique. Morrow will be placed on the 15-day DL Wednesday. ... The Blue Jays granted OF Vladimir Guerrero his release. Guerrero, who signed a minor league contract last month, had been playing at Triple-A Las Vegas. ... Toronto sent INF Yan Gomes to Triple-A. ... An MRI on Washington OF Roger Bernadina's sore right hamstring revealed no damage. Bernadina will be given two or three days off, Johnson said. ... Toronto OF Ben Francisco (left hamstring) began a rehab assignment with Class-A Dunedin Tuesday, going 0 for 2 with a walk.