CHICAGO -- Matt Wieters belted his third career grand slam with one out in the eighth inning Sunday to power the Nationals to a 9-4 come-from-behind victory over the Cubs at Wrigley Field in what could be a preview of the National League Division Series.
Washington trailed, 4-3, with one out in the eighth against Mike Montgomery when Bryce Harper singled. C.J. Edwards took over and served up a double to Ryan Zimmerman, then intentionally walked Daniel Murphy to load the bases. Edwards hit Anthony Rendon with a pitch to force in the tying run, and Wieters then launched the first pitch he saw to straightaway center for his eighth home run.
"You've got to be ready for something you can get in the air," Wieters said. "He went first-pitch breaking ball, and out of his hand I recognized it. It was something that I feel I can get in the air and it just happened to carry out."
Grand slams mean 40% off pizza

Brian Goodwin added a leadoff homer in the ninth for the Nationals, who maintained a 13-game lead in the NL East over the Marlins with the win. The Cubs have a half-game lead in the Central over the Brewers, who lost on Sunday to the Rays.

Washington took two out of three from Chicago to claim the season series, which could prove crucial, considering if the season ended Sunday, these two teams would match up in the NLDS. 
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"I don't know if we think that way," Nats first baseman Ryan Zimmerman said. "Obviously you put two and two together and you think they have a pretty good chance, but it's not like we're trying to send a message. Winning two out of three right now does nothing for us in October."
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It was a tough outing for Edwards, who Cubs manager Joe Maddon projects as a future closer.
"C.J. knows he's good," Chicago's Anthony Rizzo said. "He throws a cutter that's not easy to put the barrel on. It's just part of the season. Some guys go through it in April, May, June, July, August. There's ruts where, as a team, everyone isn't going to be clicking, and the other guys have to pick up the load. It's not any individual's fault."
Said Edwards: "I'm down on my confidence now. It happens in this game. You have to get over it and come back out and have a good successful outing my next time out to get the confidence back."
Willson Contreras did his part for the Cubs, notching his second multi-homer game in the last four days. Contreras led off the fourth with his 20th homer and opened the sixth with No. 21 to raise his RBI total to 70 for the season, tied with Anthony Rizzo for most on the team. Kyle Schwarber followed Contreras' second homer with his 18th of the season.

Contreras, who hit two home runs on Thursday against the Diamondbacks, now has 10 homers since the All-Star break, which is tied with Miami's Giancarlo Stanton for the most in the National League.
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Neither starter got a decision. Chicago's Jonathan Lester scattered six hits over 6 2/3 innings while rookie Erick Fedde, making his second career start, scattered eight hits over 5 1/3 innings.

"I was pretty happy with my stuff today," Fedde said. "I thought a lot of my pitches were working. There were just a couple mistakes that I paid for with the long ball. But at least I kept them to solo shots."

As far Chicago's Jason Heyward was concerned, this series was just another weekend in August, not a playoff series.
"It was a series we're trying to win," Heyward said. "You'd like to win, especially with how our division race is at this point. When you're playing against teams like [the Nationals], you don't have a lot of room for error. Give them more opportunities and they're going to take advantage."
MOMENTS THAT MATTERED
Stage set: The Nationals started their comeback in the seventh, when Murphy and Rendon hit back-to-back doubles to open the inning. Rendon was able to reach third when Schwarber's relay throw was off the mark and third baseman Kristopher Bryant made an errant throw. Rendon then scored on Wieters' sacrifice fly to center fielder Jonathan Jay, who slammed into the ivy-covered wall after the catch.

"I felt better with the approach that at-bat than I did the first two at-bats," Wieters said. "You never know what's going to quite get you kind of locked in a little bit more at this level. So I felt like with a runner on third, nobody out, just the focus level was turned up a little bit, and hopefully that can carry on to more at-bats."

Mistakes hurt: The Cubs took a 1-0 lead in the second on Javier Baez's RBI single, but the Nationals tied it in the third.

Wilmer Difo tripled to lead off the inning, and one out later he scored on an error by Schwarber, who couldn't get his glove on Goodwin's ball. Goodwin was credited with a sacrifice fly, and the run was earned. More >

QUOTABLE
"We kind of have a MASH unit out there. Everybody's contributing, and that helps a lot when you can take two out of three without your top starters." -- Nationals manager Dusty Baker, on winning two out of three games without their top three starting pitchers

"We didn't play a clean game overall. We made some mistakes. We're just better than that. ... We're better than that. We talk about it, we work on it, but it just has not been as tidy as it normally is." -- Maddon

SOUND SMART WITH YOUR FRIENDS
With two outs in the Cubs' eighth, Heyward doubled for his 1,000th career hit and third of the game. The Nationals' Ryan Madson stepped off the mound to give the crowd of 41,047 time to salute Heyward, who tipped his batting helmet and tapped his heart in appreciation.
"I appreciate that," Heyward said of Madson. "It was a cool gesture that he did that, but he didn't have to. I had no idea what was going on until [Brandon Hyde], the first-base coach, said something to me. I guess it's cool to have that happen at your home ballpark and do it as a Cub."

WHAT'S NEXT
Nationals: The Nats head back to Washington for the start of a nine-game, 10-day homestand. They host the Marlins for a four-game set beginning Monday night at 7:05 ET, and Max Scherzer will return to make the start after neck spasms forced him to leave his last outing early.
Cubs:Jacob Arrieta will open the three-game series in San Francisco on Monday night. He's 4-2 with a 1.82 ERA in six career starts against the Giants, including a 3-1 record and 2.08 ERA at AT&T Park. First pitch will be 9:08 CT.
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