"He was utilizing his fastball both sides of the plate, but his changeup was really good and he threw some good curveballs," manager Dave Martinez said. "When he can throw the ball the way he wants, he is nasty."
Brian Dozier and Matt Adams homered for Washington, which has won seven of its last eight and is 25-10 since May 24. The Nationals improved to 44-41, the first time they've been three games over .500 this season.
Strasburg (10-4) allowed two hits and two walks and didn't allow a man past first until the eighth. He is 20-7 with a 2.86 ERA in 34 career starts against the Marlins, and his 11 consecutive wins against them is tied with Los Angeles Dodgers ace Clayton Kershaw's dominance of San Diego as the longest active winning streak in the majors against one team.
He earned his first three strikeouts on changeups, then effectively mixed pitches throughout the night to baffle Miami's hitters. "I felt like my changeup has kind of gotten away from me," Strasburg said. "I just tried to get back to basics, and it seemed to be much better tonight."
Strasburg's gem included the first immaculate inning of his career. Strasburg needed just nine pitches to strike out Garrett Cooper, Neil Walker and Starlin Castro in the fourth. "You didn't see a lot of guys coming back feeling like they had pitches to hit," Miami manager Don Mattingly said. "Guys coming back, when they go check it, basically (said) 'He's hitting corners and basically giving you nothing to hit.' He was really good tonight."
Fernando Rodney induced a double-play grounder to escape a bases-loaded jam in the eighth, and Sean Doolittle gave up a run in the ninth but stranded the bases loaded for his 19th save in 22 tries. Miami's Sandy Alcantara (4-8), making his first start since earning an All-Star nod Sunday, matched Strasburg for five innings. But he hung a two-out, 0-2 slider to Dozier, who deposited it over the left field fence for a two-run homer in the sixth. Alcantara allowed two runs in 5 2/3 innings.
"I think I had a pretty good game," said Alcantara, who lost to Washington for the second time in a week. "I just missed a spot with my pitch and they hit a homer." Dozier's blast extended Washington's home run streak to 17 consecutive games, the longest in a half-century franchise history that includes the team's time in Montreal.
Adams added a solo shot in the eighth. TRAINER'S ROOM Marlins: OF Brian Anderson (elbow contusion) was out of the lineup and struck out as a pinch hitter in the eighth. Mattingly said Anderson, who left Tuesday's game in the second inning, was having trouble throwing. "We're hoping a couple days (helps)," Mattingly said. "There's nothing structurally going on there. It's more him banging that nerve."
Nationals: Washington placed RHP Max Scherzer on the paternity list and recalled INF Adrian Sanchez from Double-A Harrisburg. Scherzer, who earlier in the day was named the National League's pitcher of the month for June, is expected to make his scheduled start Saturday. Sanchez is hitting .330 with six homers and 24 RBIs at Harrisburg and is 4 for 17 in 16 games with Washington.
UP NEXT Marlins: RHP Elieser Hernandez (1-2, 4.07 ERA), who was 0-1 with a 9.82 ERA in six appearances against Washington in 2018, faces the Nationals for the first time this year as the three-game series concludes.
Nationals: RHP Anibal Sanchez (4-6, 3.82), who is 4-0 with a 2.29 ERA in six starts since coming off the injured list in late May, gets the nod for Washington's annual late-morning Independence Day game.
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