Tanner Roark, who is set to take the mound Friday against Cincinnati, has given up fewer than three runs in 13 of his 19 starts. (Brian Garfinkel/Getty Images)

In just his second season in the big leagues, Tanner Roark has been one of the most surprising reasons for the Washington Nationals’ success.

He holds a 2.91 ERA, the best of any starting pitcher on the team’s roster. In 1202⁄3 innings pitched, he’s recorded a 1.127 WHIP with 90 strikeouts.

“It’s just all of those weapons,” manager Matt Williams said. “He’s got the ability to change on the fly out there.”

Roark is an unlikely star, given his route to the Nationals. After a 2008 stint with the independent Frontier League’s Southern Illinois Miners, where he had a
21.41 ERA in two games, Roark was drafted by the Texas Rangers in the 25th round. He was traded to the Nationals’ system in 2010, and slowly worked his way up for a shot at pitching at the highest level. Called up in 2013, he’s since delivered with a calm demeanor and steady approach on the mound.

Roark is a top 10 player in first-pitch strikes too, according to fangraphs.com. Heading into this weekend’s series against the Cincinnati Reds, Roark ranks eighth, throwing first-pitch strikes at a 66.4 percent clip. The two-seam fastball has been his go-to since he was called up, and he’s been able to locate it superbly, confusing batters into taking the pitch inside the strike zone.

“[My approach is] attack and keep them on the defensive, and myself on the offensive,” Roark said. “Get first-pitch strikes so I can use the slider, change-up or even the fastball again.”

The 27-year-old has been the pride of Wilmington, Ill., a town with a population of less than 6,000 people, since making his Nationals debut. In a cul-de-sac of a local neighborhood, friends and family have gathered to watch the hometown hero pitch on a big-screen television.

And Wilmington has plenty to cheer for. Roark’s given up three or more earned runs in a game in only six of his 19 appearances. As Washington’s fifth starter in the rotation, he rounds out a group that’s among the best in baseball.

“He’s been a rock for us all year long,” relief pitcher Tyler Clippard said. “After watching our rotation this year, I feel we have five No. 1 starters.”

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