WASHINGTON -- Even though the Cubs have hovered around .500 this season, the Nationals are treating this four-game series as a measuring stick against the defending World Series champions. And this scene at Nationals Park is serving as a potential postseason preview, with the National League East winner currently on track to match up with the winner of the NL Central in October.
Their first meeting Monday night was a thriller, as the Cubs staved off a furious ninth-inning comeback from the Nationals to hang on for a 5-4 victory. Chicago led the game from the first batter thanks to a leadoff homer from Willson Contreras, while sparkling defense from Javier Baez and stellar pitching performances helped hold the Major Leagues' top-ranked offense scoreless for eight innings.
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Then, trailing 5-0 in the ninth, the Nats sent nine batters to the plate and rallied for four runs before Cubs closer Wade Davis struck out Ryan Zimmerman, the NL's leading hitter, to end the threat.
"I haven't faced him much," Zimmerman said. "I was just trying to get a good pitch and not do too much. The 2-2 curveball, he made a really good pitch. The 1-2 fastball away, I've got to do something with that pitch. That was the best pitch I had to hit the whole at-bat. He's not an easy guy to face.
"There's no consolation prizes or anything like that. But to come back and make it a game, I think it says something about our team."

After Albert Almora Jr.s squeeze bunt plated a run in the eighth, Chicago began the top of the ninth inning by tacking on three insurance runs off left-hander Matt Grace. The Cubs received five shutout innings from starter Eddie Butler and used seven relievers before they eventually held on for the victory to pull within a game of first place.
"Early on, guys were making a lot of great plays to keep us close," Butler said. "I really started getting locked in there halfway through the third inning. I felt I could take control of that game."

Washington spoiled another solid start from left-hander Giovany Gonzalez, who continues to state his claim to be an All-Star this season. He threw six innings of one-run ball to lower his ERA to 2.87 on the season, the third lowest in the NL behind Clayton Kershaw and Max Scherzer.
The average age of the Cubs' lineup on Monday was 24, and included three rookies.
"If this is a Spring Training lineup, we might get a call," Cubs manager Joe Maddon joked about how teams need at least four regulars in spring games.
MOMENTS THAT MATTERED
Insurance runs:  The three runs the Cubs scored in the ninth inning proved crucial, and they were also aided by a few defensive miscues. The inning began with a throwing error from Grace on a single from pinch-hitter Thomas La Stella, which allowed him to advance to second. After Grace struck out Contreras, Anthony Rizzo hit an RBI single and advanced to second after an errant throw from Brian Goodwin in left field. Ian Happ drove in another run on a single to right field and Baez capped the inning with an RBI double.

Baez thwarts Nats on defense: Baez left his imprint with a tremendous game at shortstop, filling in for the injured Addison Russell. In the third, Baez extended in the air to make a leaping catch and rob Bryce Harper of a hit on a ball hit 110 mph with a hit probability of 68 percent, according to Statcast™.

"He's a stud," Harper said. "One of the best in the league at what he does in his craft. One of the best gloves, quickest hands, lot of fun to watch him play and see how he's progressed as a player. What a stud he is."
• Cut4: Harper not pleased with Baez's robbery
Then in the eighth, Baez made one of the best plays all season. He ranged from his position at shortstop to the railing in foul territory down the third-base line to make a sliding, backhand grab to retire Adam Lind. The 132 feet he covered was the longest distance by a shortstop on a putout since Statcast™ began in 2015. 
"I don't know who else makes that play," Maddon said. "I know our guy [Russell] is really good, but [Baez] did everything so perfectly on that -- the glance at the wall, the slide, the catch, everything." More >

QUOTABLE
"It's nice before you play [Max] Scherzer -- it's always nice [to win]. To play so well and not win that game, that would've been awful, that would've been tough. Honestly, every night to me is the biggest game of the year. Tonight, playing a good team like that, playing in Washington, we have our youngest pitcher pitching against a guy who is pretty darn good. Butler beats Gio tonight … I think that's pretty good stuff." -- Maddon, on whether Monday was the biggest win of the season
"As long as you got outs [remaining], you got a chance. That's how I look at it. Especially with the offense that we have. You don't know when and who they are going to erupt against. The fact that we had action on winning that game, we were a hit away from winning that game, and our guys didn't quit." -- Nationals manager Dusty Baker

SOUND SMART WITH YOUR FRIENDS
Contreras' leadoff homer marked the ninth time in Major League history that a catcher hit a leadoff home run, and the first time since the Rays' John Jaso did on Sept. 4, 2010, at Baltimore. More >

UNDER REVIEW
Trea Turner singled to lead off the Nationals' third, and the Cubs thought they picked him off at first when Contreras threw to Rizzo at first base. Turner was called safe, but the Cubs challenged the ruling, and after a review the call was overturned.

With one out in the Chicago eighth, Baez was at first and Jeimer Candelario hit a grounder to second baseman Daniel Murphy, who flipped to Turner at short, and he threw to first. Baez was called out and Candelario was safe, but the Cubs challenged the ruling at second. After a review, the call was overturned and Baez was safe.

WHAT'S NEXT
Cubs:Jacob Arrieta gets the start against the Nationals on Tuesday. He's coming off his best outing of the season in which he held the Marlins to one run over seven innings and threw an efficient 82 pitches. His last start vs. the Nats was May 8, 2016, (no-decision). First pitch will be 6:05 p.m. CT.
Nationals: In a matchup of the past two Cy Young Award winners in the NL, Scherzer will take the mound to face the Cubs and Arrieta at Nationals Park. Scherzer has been on a roll lately, with double-digit strikeouts in six consecutive games, and he took a no-hitter into the eighth inning in his last start.
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