CHICAGO -- Ian Desmond had one of the best views of Max Scherzer at work on Wednesday.

Desmond, the Washington National's shortstop, was perched just 50 feet away as he watched the right-handed starter strike out a season-high 13 batters in seven shutout innings while the Nationals went on to beat the Chicago Cubs 3-0 in the finale of a three-game series.

"He was awesome," said Desmond, who helped with a 3-for-5 effort at the plate. "His intensity level is very high and his work ethic is second to none. The guy's an animal. It's been a real fun experience playing behind him so far."

Scherzer (6-3) scattered five hits and walked just one for his fifth straight win while the Nationals took two of three from the Cubs.

Right-hander Drew Storen worked the ninth inning for his 16th save.

"(Scherzer's) got a real good plan for everybody that he faces," said Nationals manager Matt Williams. "He's diligent about it, he takes time to work on it. He's got extra gears that a lot of people don't have. He threw one fastball at 98. When he needs to reach back he can do it."

Scherzer struck out 56 batters in his last six starts and has 85 for the season.

"You worry about how you're executing your pitches," Scherzer said. "I really feel like I'm locating the fastball well and I'm starting to get better now in executing righty-righty change ups. That's been one of my strengths through my whole career. ... Once I get that pitch going, it gives me another weapon to attack these hitters."

Chicago left-handed starter Jon Lester (4-3) suffered his first loss in six starts in a matchup between two of the big league's top pitchers, both subjects of off season free agent bidding before signing with their current teams.

"It was good, obviously Max threw the ball just a little bit better than I did," said Lester. "If you're a pitcher or just a purist of the game and like watching pitching match-ups, that was fun tonight. That was what it kind of lived up to be and I made one mistake."

Nationals right fielder Bryce Harper slammed a leadoff home run in the sixth off Lester as the Nationals opened a 2-0 lead. He is tied with Seattle's Nelson Cruz for the major league lead with 18 apiece.

Lester threw 106 pitches and worked through seven innings, allowing two runs (one earned) on seven hits while matching a season high with 10 strikeouts while walking two.

He was replaced by left-handed reliever James Russell, who faced one batter before right-hander Jason Motte came on to finish the inning.

Nationals pinch hitter Danny Espinosa made it 3-0 with his sixth homer of the season with one out in the ninth. It was the ninth solo home run of the series between the teams.

The Cubs' biggest threat came in the eighth when pinch hitter Jorge Soler greeted left-handed reliever Matt Grace with a lead-off double. First baseman Anthony Rizzo then reached after being hit by a pitch.

Grace was promptly replaced by right-hander Casey Janssen and the runners advanced to second and third on center fielder Dexter Fowler 's infield sacrifice. Shortstop Starlin Castro grounded out to end the threat.

"We did not play our best game but still had a chance to win that game," Cubs manager Joe Maddon. "I felt pretty good (about the eighth) but it just didn't play."

The Nationals scratched out a run to break the shutout in the fourth inning.

Third baseman Yunel Escobar singled, Harper walked and first baseman Ryan Zimmerman hit into a fielder's choice to second to force Harper while Escobar moved to third.

But a throw to first by second baseman Addison Russell to complete a double play went wide and Escobar successfully dashed for home.

Lester then walked catcher Wilson Ramos to put runners at first and second with one out. But he struck out second baseman Dan Uggla looking and left fielder