Looking at NLDS roster cases for Jackson, Robles, De Aza

NEW YORK - It's no secret the Nationals are using the final two weeks of the regular season to make some final evaluations of players who are in the mix for the handful of postseason roster spots up for grabs. Which makes games like Friday night's at Citi Field - a 7-6 loss to the Mets - meaningful, but in a different way than most have been all season long.

"We have the luxury," manager Dusty Baker said. "We don't like to lose, but we have the luxury of trying to find out what they can do."

So what did the Nationals learn Friday night? They learned that Edwin Jackson's case for a spot in the postseason bullpen is diminishing. They learned that Victor Robles continues to offer up evidence that he both could be a difference-maker and an inexperienced liability. And they learned that journeyman Alejandro De Aza isn't going to roll over and cede a roster spot to one of the kids.

We'll start with Jackson, who wasn't going to have any chance of cracking the postseason rotation (barring an injury to one of the top four guys), but who was making a case to be included as a long reliever after his feel-good return to the majors earlier this summer.

Those feel-good vibes, though, are floating away. After allowing six runs in 4 2/3 innings Friday night, Jackson has now allowed 23 runs in 16 innings during four September starts. He has served up nine homers in that time, with 34 total batters reaching base.

Jackson probably will get one more start next week to make a final case, but he's trying to avoid the temptation to worry about these things.

"You're not thinking about it, but everybody's pitching for a spot right now," he said. "It's no secret. When it comes to the postseason, the best people that are pitching well at the time, those will be the ones that make the roster. ... When playoffs come, you expect the manager and you expect the team to go to the hot hands. Those are vital times. You go to the people who are hot at the time."

The Nationals may not even keep a long reliever for the National League Division Series. That spot could be used instead on an extra bench player, and right now both Robles and De Aza are making cases to be considered for that role.

Robles had another electric night Friday, making only his third major league start. The highlight came on his two-run triple in the top of the fifth, the third time he has reached third base on a hit in only 15 career plate appearances (though he was called out once after oversliding the bag).

But the 20-year-old's night also ended on a sour note when he struck out against Mets closer Jeurys Familia with the tying run on third and two out in the ninth inning. Baker had the option of sending one of countless veteran regulars up to pinch-hit for Robles, but felt it was more important to see how the kid handled the situation.

"It's like: 'OK, we can't rescue them all the time. Let's see what you got and what you can do,' " the manager said. "He's been looking pretty good so far. That was a tough guy to face, Familia. But hey, you're going to face tough guys, especially if you've got a chance to make the roster here."

While disappointed with the result, Robles said he was glad Baker gave him the opportunity with the game on the line.

"I appreciate it a lot," he said through interpreter Octavio Martinez. "Because I know they have me in mind and they have confidence in me to take that at-bat."

Robles presents an intriguing option for the Nationals as a reserve in the postseason, given his speed and ability to play all three outfield positions. But De Aza provides far more experience, including experience in October. And the 33-year-old showed off some skills Friday night to remind the Nats why he should remain in the mix, as well.

De Aza tripled in the third, reached on an error in the fifth and came around to score both times. He also recorded two assists from left field, including an impressive throw from the base of the wall to second base to nab Asdrúbal Cabrera trying to stretch a hit into a double.

De Aza is batting just .154 (8-for-52) with two walks and four extra-base hits. But he said he's feeling better at the plate of late. And he has far more experience than the trio of young outfielder vying for a spot - Robles, Andrew Stevenson and Rafael Bautista.

"He looks like he's getting better," Baker said of De Aza. "He's figuring some things out. He made some outstanding plays in the outfield, and he's a guy that knows how to play. He's been around for a while. He was looking pretty good even though his average doesn't indicate it. He's a very resourceful, useful guy."

A veteran of 10 major league seasons with seven different organizations, De Aza took 23 plate appearances in the 2014 postseason for the Orioles, going 7-for-21 with three doubles and three RBIs. Because he's been there before, he feels like he knows how to handle the pressures of October.

"It's the same baseball," he said. "You just try to keep playing the same way you were playing the regular season. 'Cause if you try to do too much, it won't happen. At any level, anywhere. Just keep playing the same game, focus on the things you know how to do. And it's the same."