Patrick Corbin pitched seven scoreless innings in Sunday's win over the Royals at Nationals Park. (Katherine Frey/The Washington Post)

Consider the hot streaks throughout Patrick Corbin’s career — when he’s working fast, keeping runners off the bases and racking up strikeouts — from his years with the Arizona Diamondbacks to his debut season for the Washington Nationals. One thing becomes clear: He is most effective when he locates pitches in the lower part of the strike zone.

That sets the foundation for everything else. From there, Corbin’s options open up. He can turn to his four- or two-seam fastball, a slow curveball, a change-up or a slider, his out pitch. With his fastball command secure, he can throw other pitches for strikes and keep getting the results he wants.

That’s how Corbin produces lines such as these: Over his past four starts, he has allowed three earned runs, four walks and 18 hits over 28 innings. He has struck out 35 batters and posted a 0.96 ERA in that span.

On Sunday afternoon at Nationals Park, he threw seven scoreless innings in the Nationals’ 5-2 victory over the Kansas City Royals. He struck out the first three Royals he faced and whiffed eight more over the subsequent six innings. He allowed just five hits and didn’t walk anyone, and he has allowed one run or fewer in a career-best four straight starts.

Less than two weeks before his 30th birthday, Corbin won’t be an all-star for the third time at Tuesday’s game in Cleveland. But after a rough three-start stretch from May 31 to June 11, he has been the pitcher Washington expected when it gave him a six-year, $140 million contract, bolstering an already strong rotation alongside Max Scherzer, Stephen Strasburg and Aníbal Sánchez.

“Getting ahead, strike one, throwing competitive strikes, not walking guys,” Corbin said Sunday of his success. “Keeping them off base. Make them swing at my pitches. I feel I’ve been able to do that a lot better as of late.”

Corbin started the 2019 season hot — then cooled off for three rough outings. He has since bounced back heading into the all-star break. (Katherine Frey/The Washington Post)

Manager Dave Martinez reiterated after Sunday’s win that Corbin thrives when he establishes his fastball for strikes, especially low in the zone.

“His two-seamer was good today,” Martinez said. “His cutter was good today. He threw some really good slow curveballs. When he keeps the ball down consistently, he's really effective.”

On May 25, when Corbin threw the Nationals’ first complete game of the season, he bumped his record to 5-2 with a 2.85 ERA. But he struggled over his next three starts, at the Cincinnati Reds, San Diego Padres and Chicago White Sox. Those teams, for the most part, forced him to throw his fastball, and he didn’t locate it in the lower half of the strike zone. He rarely got hitters to swing and miss.

“Everyone wants to talk about my slider, and how effective it is, but it really can’t be without fastball command,” Corbin said June 7, a day after giving up a four-run lead in a loss to the Padres. “It starts with my fastball, even if the slider is the pitch I want to get to. I’m just not locating right now.”

Corbin’s four-game surge began June 19 against the Philadelphia Phillies. That includes a dominant start Tuesday, a day after close friend and former teammate Tyler Skaggs was found dead in the Los Angeles Angels’ team hotel. As Corbin has thrived, so have the Nationals, who entered the all-star break with the third-best record in the National League.

His default approach — “keep the ball down” — is old school in an era when many swings are designed to maximize launch angle against pitches low in the zone. Corbin makes it work by painting the corners and mixing in off-speed pitches.

And it all starts with fastball command.

“When you get strike one, strike two,” he said, “you’re putting pressure on them to swing at your pitches.”

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