SAN DIEGO -- Bryce Harper launched a go-ahead homer in the top of the third inning, and the Nationals kept mashing, using a trio of big flies to beat the Padres, 8-5, Thursday night at Petco Park.
Wilson Ramos followed Harper's two-run blast with a shot of his own, and Anthony Rendon added a 423-foot homer in the top of the sixth, as Washington became the first National League team with 12 three-homer games this season. The dingers made a winner out of Tanner Roark, who allowed four runs over six innings, while striking out five. The Nats have won each of his last four starts.
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"We got the victory to start off this road trip, which is a tough road trip," Nationals manager Dusty Baker said. "Guys are operating kind of on empty because we got in late last night [with] our body clock time being on the East Coast."

Padres right-hander Erik Johnson -- making his Petco Park debut after being acquired in the James Shields trade -- allowed five runs over six frames, including the three homers, each of which came with two strikes.
"He just didn't have that pitch to end at-bats, and that's kind of when good hitters hang around and end up getting to you -- especially if you're one side of the plate dominant," said Padres manager Andy Green. "But like I said, he was improved from the first outing, so let's keep taking steps forward."

Wil Myers went deep for the Friars, his 15th of the season, tying him with Matt Kemp for the team lead and giving him eight since the start of June, the most in the Majors. Myers, Kemp, Melvin Upton Jr. and Alexi Amarista had two hits apiece.
MOMENTS THAT MATTERED
Power alley: It began with Harper's first homer in 15 games, as the Nationals continued the power surge that has helped carry their offense, which began the day leading the National League in home runs. Harper and Ramos went back-to-back in the third inning, the ninth time Washington has done so this season. More >
"I've felt great for the past month," Harper said. "Wherever I hit the ball opposite side of the field or pull side if I can put good swings on the ball, I'll be just fine."

Wil power: Myers' fifth-inning home run was an absolute rocket off the facing of the Western Metal building's first deck. It left his bat at 113 mph, according to Statcast™, marking the highest exit velocity for a Padres hitter this season. Myers held the previous top mark with a 112.4 mph single in Colorado in April. More >
"I squared that one up pretty well," Myers said, when asked if it was the hardest he's ever struck a baseball. "I've hit some balls pretty far that I'd like to know how hard those were. But as far as exit velo, possibly that was the hardest."
And the closer is? Nationals manager Dusty Baker said before the game that he was ready to end the "bullpen by committee" experiment and start to work players into regular roles. Baker named Shawn Kelley his closer after the game, during which Kelley pitched the ninth inning to record his second save since Jonathan Papelbon landed on the DL. More >
"We think he's best suited for that until Pap gets back," Baker said.

Start me up: The first three Padres hitters all reached base in the bottom of the first, leading to a pair of runs on singles by Kemp and Upton. The Padres have now scored 21 times in the first inning in their 15 June games.

QUOTABLE
"He's tall and he jumped high. It was a good catch. He's played a good first base. He's been very solid at first base. For a guy that hadn't played it really prior to this season, he's continued to take steps forward." -- Green on Myers' snare of a Stephen Drew liner in the top of the eighth

REPLAY REVIEW
After the Nationals opted not to challenge Upton's steal of second base in the bottom of the sixth, the Padres left fielder attempted another steal as he took off for third and was called out. The throw clearly beat Upton, but replays showed that Rendon's tag did not make contact with Upton's ankle until just after he had reached the bag. Upton -- who was so confident of a safe ruling that he never left the base -- would score one pitch later on Christian Bethancourt's RBI groundout.

WHAT'S NEXT
Nationals: Joe Ross will take the mound Friday night for the Nats to make his second career start against the team that traded him in December 2014. Ross carries a 3.01 ERA into this outing and has finished the seventh inning in three of his last four starts. First pitch is slated for 10:40 p.m. ET. 
Padres:Christian Friedrich gets the ball for the Friars Friday night in the second game of a four-game set against the Nationals. First pitch is slated for 7:40 p.m. PT. Friedrich, whose rotation spot was in jeopardy a month ago, has posted a 1.82 ERA over his last four starts.
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