Who makes the Nationals' NLDS roster?

The Nationals have until Friday morning to set their 25-man roster for the National League Division Series. And given some of the down-to-the-wire decisions they need to make, they might just use every remaining minute available to them before submitting that roster to Major League Baseball.

First and foremost, of course, is the state of Max Scherzer's right hamstring. The ace insists he'll be pitching in this series, but the Nationals won't know for sure when he'll pitch until after he throws off a bullpen mound today and tests that leg.

If they are uncertain in any way about Scherzer's health, the Nats might feel the need to carry a true long reliever in their NLDS bullpen, someone who could be counted on to provide four or more innings in an emergency situation, such as A.J. Cole, Edwin Jackson or Matt Grace.

If, on the other hand, the Nationals are confident that Scherzer is OK, they could decide to forego the long man and instead carry an extra bench player for the series against the Cubs. Options for that job would include rookies Victor Robles and Adrián Sanchez, veteran Alejandro De Aza or a third catcher (with both Jose Lobaton and Pedro Severino making the squad).

Then again, before anything else the Nationals have to decide if Brian Goodwin is ready to return to the active roster after missing the last 7 1/2 weeks with a strained groin. The rookie outfielder spent last week getting at-bats at the instructional league in West Palm Beach, Fla., then rejoined the club Friday at Nationals Park and appeared healthy and good to go.

Suffice it to say, when Dusty Baker, Mike Rizzo and their respective staffs meet to finalize their NLDS roster, they aren't going to be making clear-cut, rubber-stamp decisions. There's going to be some debate.

How, though, might the final 25-man roster look? Here's a breakdown ...

STARTING PITCHERS (4): Stephen Strasburg, Max Scherzer, Gio Gonzalez, Tanner Roark

This part is easy. The only question is when Scherzer starts and how that affects the other guys. Best guess: If he emerges from today's bullpen session well, Scherzer starts Game 2, with Strasburg starting Game 1, Gonzalez and Roark starting Games 3 and 4 at Wrigley Field and then both Strasburg and Scherzer available for a potential Game 5 back at Nationals Park.

RELIEVERS (7): Sean Doolittle, Ryan Madson, Brandon Kintzler, Matt Albers, Oliver Pérez, Joe Blanton, Sammy Solís

The first five names are locks, given their performance as long as they've been part of this year's bullpen. Doolittle is the closer. Madson pitches the eighth inning. Kintzler pitches the seventh. Albers and Pérez pitch earlier or are brought in for key matchups elsewhere. Blanton and Solís aren't locks, but both pitched well down the stretch after ragged first halves. Both have postseason experience. And both have the ability to go multiple innings if needed.

CATCHERS (2): Matt Wieters, Pedro Severino

Wieters obviously is the starter and will be behind the plate for every postseason game if healthy. The debate will be over his backup, and there's a compelling argument to keep Severino over Jose Lobaton. If Wieters is being replaced in a game, it most likely will be for a pinch-runner. Severino runs well for a catcher. Why burn up two players to replace Wieters if you can get by with only one?

INFIELDERS (6): Ryan Zimmerman, Daniel Murphy, Trea Turner, Anthony Rendon, Adam Lind, Wilmer Difo

The four starters are set, and the two backups are locks to make the NLDS roster. Lind will be Baker's top left-handed bat off the bench and be available to play first base if Zimmerman can't go for some reason. Difo will back up the three other infield spots and could get some pinch-hitting opportunities when the Nats need to start a rally or move a runner up.

OUTFIELDERS (5): Jayson Werth, Michael A. Taylor, Bryce Harper, Howie Kendrick, Brian Goodwin

Is Werth's starting job in left field secure? Could Kendrick get the nod instead? The thinking here is that Werth gets first crack at it, given his experience and clout, and given Kendrick's experience coming off the bench. But Baker's leash on Werth should be short. And if nothing else, Baker needs to acknowledge that the 38-year-old needs to be replaced defensively late in games. That's where Goodwin's likely return becomes critical. He can back up all three outfield spots, but his primary role in this postseason could be to play left field late with a lead.

You'll notice that only adds up to 24 players. There's still one more slot. And this is where things get tricky. Essentially, the Nationals need to decide whether to keep an eighth reliever or a sixth bench player. And they could go in several directions here.

If they think they need another reliever, they could go with a long man like Cole, Jackson or Grace. Or they could go with another matchup lefty in Enny Romero.

If they think they need another position player, they could go with a third catcher. Or they could go with a young infielder or outfielder (Robles, Sanchez, Rafael Bautista) or a veteran outfielder (De Aza).

So who gets it? In a perfect world, the 25th spot would be used on a speedster who plays good defense. In other words, Robles. But the Nationals probably can't afford to use that spot on such an inexperienced player, no matter how talented he is. If there's concern about Goodwin's healthy, De Aza would be the logical backup outfielder choice.

But the biggest concern right now might well be Scherzer's hamstring. Unless the Nationals are nearly 100 percent convinced their ace is fine, the safest choice is to keep a long reliever. Given the performances down the stretch of the available choices, Cole (3.00 ERA in September) gets the nod here.