WASHINGTON (AP) After a nail-biting victory over the NL East leading Washington Nationals, Chicago Cubs manager Joe Maddon still cringed to consider what could've happened.

He almost found out after the Nationals scored four runs in the ninth before Wade Davis struck out big league batting leader Ryan Zimmerman with runners on second and third to blunt a comeback bid, and Cubs preserved a 5-4 victory in the opener of a four game series Monday night

''To play so well and not win that game, that would have been awful,'' said Maddon. ''That would have been tough.''

In jeopardy of being shut out for the first time this season, the Nationals' comeback began against Hector Rondon and continued when Davis became the Cubs' eighth pitcher of the game.

With Washington down 5-3, Bryce Harper's single and third hit of the game loaded the bases with two outs. Davis threw a wild pitch that scored a run before striking out a swinging Zimmerman, who's hitting .344. The final pitch bounced, and catcher Willson Contreras zipped a low throw to first baseman Anthony Rizzo to close out the victory.

''We pitched really well but arguably one of our best pitchers had the roughest night,'' Maddon said. ''The add-on runs in the ninth inning were large once again.''

Said Zimmerman: ''He's been one of the best in the game for a while and he still is. I had one good pitch to hit, and usually that's all you get against guys like that.''

Contreras hit a leadoff home run in his first career game-opening at-bat and Eddie Butler (4-2) worked five scoreless innings to keep the Cubs ahead.

Gio Gonzalez (7-2) allowed a run and two hits, striking out eight over six innings in his sixth start. Afterward, he was more excited about his offense's comeback.

''We were kicking (butt) in the ninth inning, giving them something to bite their nails about,'' he said. ''We were fighting all the way until the end and showed that (we have) a stronger way of thinking from last year to this year.''

Rizzo began the day in a 2-for-20 rut, so Maddon moved the big first baseman out of the leadoff spot and put another unlikely hitter there. It paid off immediately when Contreras hit his eighth homer, a drive about 10 rows deep into the seats in left.

Chicago made it 2-0 on Albert Amora Jr.'s squeeze bunt single in the eighth. The Cubs scored three more in the ninth, capped by Javier Baez's two-run double. The shortstop struck out three times before singling and scoring on Amora's squeeze.

''He came back with two knocks,'' Maddon said. ''That's beautiful.''

BUSY BAEZ

Baez made two exceptional plays at short, diving to snatch Harper's liner in the third, then racing a long way into foul ground to make a sliding catch on Adam Lind's popup in the eighth.

''When the ball was coming down I was really was kind of worried about the wall and I saw the ball last second and it just went in my glove,'' he said of the latter. ''I really don't know how I catch it. I just ran hard over there and never gave up.''

PITCH AT OWN RISK

Harper had his second three-hit game in a row. It came against a Cubs team that walked him 10 times - four intentionally - in a series at Wrigley Field in May of 2016.

''I think last year is last year, and what we're doing this year, we're going to try to keep it going,'' Harper said. ''Zim's done a great job for us, and (Daniel) Murphy as well. I mean 1 through 8, pick your poison.''

PLAY ME ANYWHERE

Contreras said he wasn't fazed when he saw Maddon had inserted him into the leadoff spot.

''Everybody knows how he likes to work,'' Contreras said. ''Everybody needs to be ready for every spot.''

TRAINER'S ROOM

Cubs: SS Addison Russell struck out as a pinch hitter, a day after making an early exit before of a sore shoulder. Maddon said Russell's injury is ''not serious, but I don't want to push it.'' For some infield depth, Chicago recalled INF Jeimer Candelario (who started at third) from Triple-A Iowa and optioned RHP Dylan Floro there.

Nationals: LF Jayson Werth has been taking swings in BP and is getting closer to a rehab assignment. ''I'm not quite there, but I'm definitely improving,'' he said.

UP NEXT: The series continues Tuesday when Washington's defending NL Cy Young Award winner Max Scherzer (7-1, 2.96) and Cubs 2016 All-Star Jake Arrieta (7-5, 4.36) both go in search of their third win in June.

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