Tanner Roark. (Photo by Jonathan Newton / The Washington Post)

brushback_harperTanner Roark was, again, strong on Tuesday. He gave up two runs on five hits over 6 1/3 innings against the Mets. He is four outs away from reaching 200 innings for the first time at any level of his career. He notched his 15th win. His ERA is down to 2.85, 17th best in baseball and 11th best in the NL. His ERA is better than pitchers with more pedigree, such as David Price, Jeff Samardzjia, James Shields and Max Scherzer. Roark is worth 5.2 WAR in Baseball-Reference.com’s version.

And yet, with the playoffs starting in about a week, Roark could be the odd man out in a likely four-man rotation. How many five-win-above-replacement-level/sub-3.00-ERA starters end up in the playoff bullpen?

But that’s the situation the Nationals could be facing. Gio Gonzalez has the experience. He has been one best left-handed starters over the past several years. He dealt with his first-ever shoulder injury this season and, over his past seven starts, has a 3.09 ERA and walked only nine in 43 2/3 innings. He would be the only left-hander in a playoff rotation and, depending on the first-round opponent, that could be important.

Roark, on the other hand, has been one of the Nationals’ best four starters, and one of the most surprising stories of the season. But he has never pitched this much or deep into the season before. He has experience pitching out of the bullpen — and well, too — and that versatility could hurt his argument as a starter.

The even-keeled Roark, who is rarely fazed on the mound, insists he hasn’t thought about his postseason status. He likely has one more regular season start left, in line to start the season finale.

“You gotta just keep doing your job,” Roark said. “Go out there each day and work hard each day in between your starts and go out there whenever you name is called. Just go out there and do your job.”

Manager Matt Williams said the team is still discussing the playoff rotation and no decision has been reached. (“There’s going to be some really late nights the next three or four days,” he said before Tuesday’s game.) But, some order of Stephen Strasburg, Jordan Zimmermann and Doug Fister seems obvious as the first three starters. The fourth spot is the toughest.

It would, perhaps, be easier if one starter wasn’t pitching well, but all five starters have been strong. Since the start of August, here are their ERA’s: Strasburg (2.51), Zimmermann (2.06), Fister (2.37), Gonzalez (3.48, but better of late) and Roark (3.09).

“It says that they work hard,” Williams said. “And that they’ve been resilient all year, first and foremost, because you get to this time of year, you’ve got guys pushing 200 innings, you’ve got Tanner going to places he’s never been before. It’s important for them to stay strong and do their work in between starts. They all do that. And it’s important for them to compete. When they go out there, they compete.

“It makes for tough decisions but those are good, tough decisions. You would not want that decision made for you this time of year. You want to be able to say, ‘Boy this is a hard one.’ That’s a good thing for us. They’re all pitching really well.”

But once a decision is reached and one of those starters is pushed to the bullpen, will that player understand?

“At this point in the year, not everybody will like it but everybody will understand,” Williams said. “We are all on the same end of the rope. And everybody must do their part for us to get to where we want to get to.”

Roark views his time in the majors as a blessing. Over 14 months ago, he was at Class AAA Syracuse and 26 years old. The year before that, he had a 4.39 ERA there. Now, he has been one of the best starters on the best team in the NL, a heartwarming story of perseverance. He had the temperament to turn around his minor league career and survive in the majors when little was expected or known about him. He understands that difficult choices have to be made and that someone will be left out.

“They make the decisions and whenever our name is called we pitch,” Roark said. “That’s what my mentality is and that’s what everybody else’s mentality is.”

FROM THE POST

The Nationals inch closer to the top seed but Denard Span gets banged up in a 4-2 win over the Mets.

For some Nationals — Stephen Strasburg, Kevin Frandsen, Scott Hairston and Co. — the first time in the playoffs feels like a charm.

Since 2000, the team with the NL’s best record has only made the World Series twice. On the perils of the top seed, by Thomas Boswell.

FROM YESTERDAY’S JOURNAL

Denard Span exits Tuesday’s game after apparent injury

Nationals considering an extra day for Jordan Zimmermann

Nationals exercising caution with Ryan Zimmerman’s hamstring

Evaluating Anthony Rendon’s NL MVP candidacy

NATS’ MAGIC NUMBER TO CLINCH BEST NL RECORD

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