PHILADELPHIA -- What once appeared as the Nationals' toughest roster decision heading into the postseason has become much more clear, with Bryce Harper set to return from the disabled list as early as Tuesday in Philadelphia.
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Still, with Game 1 of the National League Division Series on Oct. 6, the Nationals have a few things to consider.
The Nats carried 11 pitchers and 14 position players during last season's NLDS, electing to carry an extra bench player over an extra reliever. These final few games of the regular season are serving as an audition of sorts for some players in the running for the final roster spots, although manager Dusty Baker said he will balance recent performance and track records to determine how to best fill out the roster.
Here are the top five roster decisions the Nationals face before the postseason begins:
1. Has top prospect Victor Robles done enough to make the roster?
Robles, the team's top prospect and No. 2 in baseball according to MLBPipeline.com, was initially promoted to Washington to provide more outfield depth in September. It was also a way to ease him into the Majors when he was set to be added to the 40-man roster next year anyway.
Then, Robles stepped on the field and looked like he belonged, putting himself firmly in contention for a spot on the postseason roster even though he is only 20 years old. He has already recorded two of the team's three fastest triples ever tracked by Statcast™. Robles made a pair of good defensive plays in right field during his most recent start, Sunday at Citi Field. He has not looked overwhelmed.
"I feel great. I feel fine, relaxed," Robles said through an interpreter Friday. "I feel like this is the league I've been playing at all year."
Robles' blazing speed looks enticing as a pinch-runner off the bench and he could serve as a solid defensive replacement in the outfield as well. The lone question remaining for Robles is whether he has shown enough in eight Major League games and 20 plate appearances to earn a roster spot.
2. Who will get the last bullpen spots?
The Nationals' bullpen has dominated most of the conversation around the team this season as it transformed from a first-half disaster to solid in the second half, thanks to three acquisitions before the July 31 non-waiver Trade Deadline. Sean Doolittle, Ryan Madson and Brandon Kintzler are locks to make the postseason bullpen, along with right-hander Matt Albers and left-hander Oliver Perez, who have pitched well all season.

Left-hander Sammy Solis has emerged recently and recorded nine consecutive scoreless appearances with a 1.42 ERA and 14 strikeouts in his last 14 appearances dating back to Aug. 13. That should be enough to earn him a spot. The remaining spot(s) will be determined from right-handers Joe Blanton and Edwin Jackson, and left-handers Enny Romero and Matt Grace.
3. Who will play left field?
Jayson Werth is the team's emotional leader and is in the final season of his seven-year contract in Washington. He has been the team's starting left fielder, but has struggled since missing nearly three months with a broken foot. Meanwhile, all Howie Kendrick has done since being acquired before the non-waiver Trade Deadline is hit, owning an .823 OPS and six homers in 48 games with the Nats. Adam Lind, who is left-handed, has been even better, with an .894 OPS and 14 homers this season. Will the Nationals continue to play Werth every day? Or will they figure out some sort of platoon in left field to best utilize all three players?

4. Can Brian Goodwin or Stephen Drew return in time?
Harper is not the only player with aspirations of returning to the field during the season's final week as Drew (abdominal) and Goodwin (groin) have been taking batting practice, playing in simulated games and working out with hopes of returning before the season ends. It is unclear whether Washington will clear either to play and if so, that they will be able to prove enough in limited playing time to make a playoff bench.

5. Who will fill out the bench?
Lind and Kendrick are certainties. Wilmer Difo is likely to serve as a backup infielder and somewhat of a utility player. That leaves the backup catcher's role, which has been Jose Lobaton this season even as he has struggled offensively. Pedro Severino could replace him, because he is a better hitter and baserunner, or serve as the third catcher if Washington carries an extra bench player. The Nationals will likely need another outfielder and true backup center fielder, which could be Robles, Rafael Bautista or Andrew Stevenson. And if Drew or Goodwin return before the end of the regular season they could also be in the mix.