WASHINGTON (AP) -- After Stephen Strasburg failed to get out of the fifth inning in his second start this season, he had a little chat with Nationals teammate Ian Desmond about changing his approach on the mound.
''It was just: I don't need to go out there and trick guys, and I don't need to go out there and be perfect,'' Strasburg recalled. ''I just got to attack the strike zone, let my stuff work.''
Consider it done. In his third - and by far the best - outing of 2014, Strasburg struck out 12 in 6 2-3 innings on a day Washington really needed to rest its relievers, and Desmond and Jayson Werth homered, leading the Nationals past the Miami Marlins 7-1 Thursday for a three-game sweep.
''We actually talked after his last start, and he told me some things that he wanted to work on. And to see him go out and execute it today, exactly the way he wanted to change and what he was going to mess with, was pretty good to see,'' said Desmond, whose grand slam off reliever Arquimedes Caminero in the eighth broke open a tight game. ''That's maturity. Everyone forgets how young he is. He's going to keep on getting better and better and today was proof of that.''
The 25-year-old Strasburg (1-1) got 14 consecutive outs in one stretch and allowed only three hits, including Marcell Ozuna's homer in the seventh. The right-hander's lone walk was to the last batter he faced.
Washington's starter Wednesday, Jordan Zimmermann, left after a career-low 1 2-3 innings, leaving the bullpen ''taxed,'' as manager Matt Williams put it. The Nationals won that game 10-7 on Werth's go-ahead grand slam in the eighth, and this time he connected in the third - a two-run shot off Tom Koehler (1-1) that put Washington ahead 2-0.
Werth hit a 3-0 pitch just to the left of straightaway center. After driving in a total of one run over the season's first seven games, Werth has seven RBIs in the past two.
''Got the green light from Matty,'' Werth said, referring to the manager. ''Got a pitch up that was elevated and put a good swing on it.''
Said Koehler: ''Got to do a better job of ... executing.''
Strasburg lasted 4 1-3 innings in his previous start, a 6-2 loss to Atlanta on Sunday, and he entered Thursday 0-1 with a 6.10 ERA. But with the temperature 67 degrees at the unusual 4:05 p.m. start, and shadows creeping across the diamond, he was much better against Miami, mixing a 95-96 mph fastball with a seemingly unhittable changeup.
''You have to be in swing mode, expecting fastball, certainly,'' Williams said. ''His changeup was really good off of it today and he used it a lot.''
Some Marlins hitters did say the shadows were problematic.
''It was kind of tough to see out there,'' said Derek Dietrich, who was 0 for 3.
Still, the outset was inauspicious for Strasburg. Christian Yelich led off the game with a single up the middle, stole second and took third on an error. But he got caught in a rundown when he tried to head home on Dietrich's comebacker.
There wasn't another baserunner for Miami until shortstop Desmond booted Adeiny Hechavarria's grounder for an error in the fifth. But Strasburg struck out Jeff Mathis looking at a 95 mph fastball to end the inning, then hopped off the mound.
In the sixth, the Marlins' best hitter, Giancarlo Stanton, faced Strasburg with two aboard and one out in a 2-0 game.
''Any ball he puts in play can take somebody's head off,'' Strasburg said.
But Strasburg struck out Stanton looking, then got cleanup hitter Garrett Jones swinging at a high fastball for his 10th K - the 13th time the No. 1 overall pick in the 2009 amateur draft had at least that many in a game.
Stanton's next at-bat came in the eighth against rookie Aaron Barrett, who struck him out with a slider.
''He's a bulldog,'' Strasburg said about Barrett. ''He's not scared of anybody.''
NOTES: Nationals pitchers struck out 17 Marlins batters, tying both franchises' records. ... The Nationals open a three-game series at Atlanta on Friday, with RHP Tanner Roark (1-0, 3.00) facing Braves RHP Julio Teheran (1-1, 2.77). The Marlins head to Philadelphia, where RHP Jose Fernandez (2-0, 0.71) will start against Phillies RHP A.J. Burnett (0-1, 3.86).
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