WASHINGTON -- From the very first pitch Stephen Strasburg threw on Saturday afternoon, the Diamondbacks hitters were all over him. Ketel Marte deposited a first-pitch 92-mph fastball into the bullpen in right field, giving Arizona an early advantage and setting the tone for the rest of a 10-3 Nationals loss at Nationals Park, where both teams combined to hammer six homers in the first four innings and seven on the day.

Strasburg surrendered four of those homers (all solo), matching a career high and marking only the second time in his career he has allowed that many long balls (Aug. 8, 2014). It was an overall uncharacteristic outing for Strasburg, who allowed runs in each of the first four innings, and a leadoff homer in three frames.

“I think when you make mistakes here in the big leagues, you give them a much better chance to barrel it,” Strasburg said. “And they barreled it.”

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The D-backs made Strasburg pay for anything that caught too much of the plate during his five innings of work. They collected nine hits overall, the most he has allowed since Aug. 17, 2016, a span of 65 consecutive starts. Six of those nine hits went for extra bases, which also matches a career high. Strasburg had owned the third-longest streak of allowing eight hits or fewer in a start.

Most of the damage was done against Strasburg’s four-seam fastball. Arizona went 5-for-9 with three homers and a triple in at-bats ending in a fastball. They even had success against the two-seamer, going 2-for-3 with a pair of singles. And Strasburg’s curveball got punished by Christian Walker to start the third inning, the first time since August 22 of last year he has given up a homer on that pitch.

“When he's really good, he mixes in all his pitches,” manager Dave Martinez said. “Today, I think he was trying to find that fastball, that location and it just wasn't there.”

Strasburg acknowledged that he felt like he was flying open in his delivery during the game, which hindered his ability to command his fastball. He tried to correct the issue throughout the game, but was unsuccessful.

“You go with what you have during the game, obviously, and you just keep pounding away,” Strasburg said. “I did the best I could with what I had today, but I need to make some adjustments, obviously.”

The outing was even more unusual for Strasburg because he has had success this season keeping the ball in the ballpark. Entering the game, he had allowed only eight homers in his first 14 starts and just two since the start of May.

And Strasburg had been so reliable lately. In his last five starts, he had gone 4-0 with a 2.91 ERA before Saturday’s clunker. That made it easier to dismiss this as a blip in an otherwise stellar season for Strasburg. And an outing he will be eager to put behind him.

“I think everybody would say that’s not the Stephen that we’ve seen the past couple starts,” first baseman Matt Adams said. “He’s a bulldog. He wants the ball and goes out there and tries to get the job done.”