WASHINGTON -- The Nationals and Pirates entered this series ranked first and second, respectively, in September bullpen ERAs. And yet on Thursday night, the Bucs struck for two in the top of the ninth inning to tie the game before Alejandro De Aza singled home the game-winning run in the bottom half for a 5-4 Nats walk-off victory at Nationals Park.
De Aza, who replaced Howie Kendrick (hamstring tightness) in the third inning, also drove in the go-ahead run in the seventh before he came up with the game-winning hit in the ninth against Pirates right-hander Daniel Hudson.
"I'm happy," De Aza said. "It's something that I'll always want to do, to contribute to the team. It's all about winning."
De Aza's heroics were needed after Josh Bell hit a two-run tying homer off Nationals closer Sean Doolittle, who blew his first save opportunity since joining the club this summer. Doolittle had been 21-for-21 on save chances with Washington this season.

"Now you can start all over again," Nationals manager Dusty Baker said. "And better now than later. ... If he goes 21 more, that means we'd be world champions."
There are just three more games remaining at the end of the regular season before the Nationals begin their National League Division Series matchup with the Cubs. But Baker does not want to overlook this series with the Pirates. He plans to use this weekend to get some players sharp and healthy while also make some final judgments to determine his club's postseason roster.
Right-hander Edwin Jackson gave the Nats something to think about as he stated his case for the postseason bullpen with six innings of two-run ball, to go along with seven strikeouts and two walks.

Pittsburgh lost its starter, right-hander Ivan Nova, after he was struck on his right index finger during a bunt attempt in the third inning. X-rays on Nova's pitching hand were negative, but his exit set up an early entrance for right-hander Tyler Glasnow, who issued five walks in 3 2/3 innings of one-run ball.

"Disappointed, man. It's not the way you want to finish the season," said Nova, who set a career high by making his 31st start. "I really came today prepared to have a good game. Unfortunately we end it like that. It's my first time getting hit. I know how the guys feel now when they get hit."
MOMENTS THAT MATTERED
Paying for free passes: The Nationals had drawn seven walks on the night and had little to show for it until a seventh-inning triple from De Aza made right-hander Dovydas Neverauskas pay for a walk to Anthony Rendon. De Aza has played well lately, and because he provides a potential veteran presence, he could be in consideration for the postseason roster.

"You're constantly changing your mind and kind of asking yourself questions and everyone questions of what's going to be our best roster," Baker said. "He had a great game tonight. He's made some great adjustments at the plate and he plays good outfield. Good baserunner. That was a big night for him."
Baker did not sound concerned about Kendrick's hamstring, which tightened up on him before the game and did not get better. The Nationals will monitor Kendrick closely the next few days.
Robles leaves 'em loaded: This weekend will also be an opportunity for the Nationals to judge their young players in high-leverage spots. In the sixth inning they had the chance to see Victor Robles, the organization's top prospect as rated by MLBPipeline.com, come to bat with two outs and the bases loaded after Glasnow issued three walks. Pittsburgh called upon right-hander Edgar Santana, who struck out Robles to end the inning.

"It's hard to walk five guys up here and not get scratched," Pirates manager Clint Hurdle said. "Santana did a nice job of cleaning that inning up."
QUOTABLE
"Look [at three strikeouts in three at-bats] on the left side tonight, and all of a sudden he goes from hot to not. Then you flip him over right-handed, and he hits one of the better closers in the league out of the ballpark. He's that guy where you don't want to go to the bathroom or walk away when he's up to the plate. You don't know what you're going to miss." -- Hurdle, on the switch-hitting Bell's game-tying homer
SOUND SMART WITH YOUR FRIENDS
Bell's home run was his 26th of the season, tying the Pirates rookie record set by Jason Bay in 2004. He is now one homer shy of the Major League record for most home runs by a switch-hitting rookie, currently held by Eddie Murray (1977).
"It's definitely awesome," Bell said. "It's something for me to look back on the next couple weeks and really exhale and realize what I've done."
Pirates rookie Christopher Bostick, a former Nats prospect, recorded his first career RBI on a double to center field in the third inning.

JACKSON DELIVERS FOR GRANDMA
Jackson revealed after the game that it was an emotional outing for him. The veteran's grandmother, Julia, passed away a few days ago, and it meant even more to Jackson to pitch well thinking about her in what will be his final start this year and perhaps his final appearance in a Nationals uniform.
"Matter of fact, she probably got the baseball package just to watch games," Jackson said. "That made tonight's start a little bit more special to give the family something positive to deal with and something as far as myself as well, just to know she's in heaven looking down and finish up like this."
AFTER FURTHER REVIEW
Robles nearly had his first stolen base in the fifth inning after he reached first on an infield single to shortstop. Robles took off for second on the next pitch and beat the throw, but the Pirates issued a challenge, seeing that Robles' foot came off the bag briefly. The call was overturned and Robles was called out.

WHAT'S NEXT
Pirates: Right-hander Gerrit Cole will make his 33rd and final start of the season as the Pirates continue their season-ending series against the Nationals on Friday at 7:05 p.m. ET at Nationals Park. Cole is 2 1/3 innings shy of 200 and within 11 strikeouts of his second 200-strikeout season, but also one home run away from tying the club record of 32.
Nationals: After taking an off-day Thursday, Bryce Harper should return to the lineup to continue preparing himself for the postseason when the Nats host the Pirates for the second game of this series. Right-hander Stephen Strasburg will take the mound for his final start before the postseason.
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