WASHINGTON -- With their bullpen exhausted from the past two days, and ineffective for the entire season, the Nationals needed Stephen Strasburg to pick them up on Saturday night against the Cubs.

And Strasburg delivered, twirling one of his best and most efficient outings of the season to lead Washington to a 5-2 victory at Nationals Park. He required 93 pitches to complete eight innings, limiting Chicago’s red-hot offense to two runs (one earned) and scattering four hits with no walks and seven strikeouts.

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Perhaps Strasburg had a chance to throw his third career complete game, but after throwing 97 and 106 pitches in his previous two outings, manager Dave Martinez decided he had gone far enough -- and Strasburg agreed.

“We got a great closer, so didn’t want to hold that from him,” Strasburg said. “... I think it’s important that you focus on the now, and you focus on that one pitch that you got to make. You go as long as you can until Davey takes the ball out of my hand.”

Strasburg outdueled Jon Lester, who carried a 1.16 ERA into this start, thanks to some early help from his offense. Brian Dozier ignited the Nationals with a solo home run in the second inning, his fourth of the season, and Howie Kendrick and Juan Soto hit back-to-back RBI doubles in the third.

Soto added an RBI single with one out in the fifth to chase Lester in a rare off outing.

Strasburg’s performance carried the Nationals into the ninth inning, where the only reliever necessary was Sean Doolittle. The closer tossed a scoreless ninth to seal the victory, although the game was played under protest after Cubs manager Joe Maddon took issue with Doolittle’s pitching motion.

Strasburg continued his mastery over the Cubs in his career; he owns a 2.05 ERA in seven regular-season starts against Chicago, and that doesn’t include his performance in the 2017 National League Division Series (no earned runs in 14 innings).

The opposing team has hardly mattered for Strasburg lately, however, as he has settled into a groove with this recent stretch. He has now pitched six or more innings in nine of his 10 starts this year, matching Justin Verlander and Zack Greinke as the only pitchers in baseball with as many such outings. In his last six starts, including Saturday, Strasburg has posted a 2.13 ERA with a strikeout-to-walk ratio of 54-to-9.

“When he’s on, you can tell that he uses both fastballs -- two-seamer, four-seamer -- and today was curveball, changeup,” Martinez said. “But he gets ahead of hitters, and when he does that, gets ahead, he’s tough.”

Strasburg is doing so by attacking hitters in a variety of different ways, sometimes seemingly reinventing himself from start to start.

Overall, Strasburg is using his four-seam fastball less frequently than ever, throwing it just 49.3 percent of the time this season, the first time in his career that number has dropped below 50 percent (his career usage rate is 58.6 percent). In exchange, he is throwing his curveball at a career-high 30.9 percent of the time, and opposing hitters entered the game batting .103 with a .121 slugging percentage against it.

But on Saturday, Strasburg flipped the script. He relied more heavily on his fastball, tossing it for 38 of his 93 pitches and generating seven swings and misses while getting seven called strikes with his four-seamer. He started the Cubs with a steady diet of fastballs early and then began mixing in his offspeed pitches late in the game.

“It’s important to kind of use everything,” Strasburg said. “If they want to be aggressive, great. You kind of just got to continue with the execution and using your defense.”