Ricky Carioti/WP

Kris Medlen’s 13-strikeout performance overshadowed Ross Detwiler last night, but then that is nothing new for Detwiler. All season, he has been portrayed as the fifth wheel of the Nationals’ powerful rotation, a spare tire to the team’s other four starters. “Nobody really talks about him,” catcher Kurt Suzuki said.

But as September churns along and the playoffs approach, Detwiler’s importance to the Nationals’ postseason hopes is coming into focus. After he allowed the Braves one run over six innings last night, Detwiler’s 2.86 ERA since the all-star break leads the Nationals’ staff.

“Man, he’s just good,” Braves catcher David Ross said. “It seems like he gets better and better each time we face him.”

Detwiler’s start last night featured a key step for him: the return of his curveball. For most of August, Detwiler pitched almost exclusively with his fastball. In August, 90.1 percent of his pitches were fastballs. The next highest in the National League was Gio Gonzalez, who threw 74.9 percent of his pitches for fastballs.

“I know my fastball is pretty good, and I can get outs with the fastball,” Detwiler said. “I get really [ticked] off when I get beat by my secondary pitches. And I didn’t have as much confidence” in offspeed pitches.

Detwiler succeeded with his fastball-only attack. But he wouldn’t be able to sustain the success. Eventually, hitters would catch on, start sitting on fastballs. 

“When you’ve got a good fastball like he does, he tends to fall in love with it a little bit,” Suzuki said. “I think that throwing that other offspeed stuff is only going to help him. You got to find that happy medium. It’s always a learning process. You got to find what works and you got to keep making adjustments.”

In his previous start, Detwiler threw more changeups and felt much better about them. This week, on the night before he threw a bullpen session, Detwiler focused on his curveball. “I kind of started thinking about why,” Detwiler said. “I had a good one in the past, especially in college. It’s the same arm and everything. So why is it different? It should be better. I started thinking about things.”

In the bullpen, Detwiler focused with pitching coach Steve McCatty on improving his curveball. He realized when he took the ball out of his glove, he cupped his left wrist immediately. The delivery robbed him of sharp break and allowed hitters to recognize the pitch too easily.

“I was starting it too early instead of letting my arm be loose,” Detwiler said. “That’s why I didn’t have any feel for it. I didn’t know whether it was going to break a lot. Usually it stayed up in the zone and got hammered.

“It makes me freer. I feel like I have a good finish on it. I can feel where the ball is going to go. It’s still kind of a work in progress. Some of them are good, and some aren’t.”

Detwiler felt confident enough last night in his curveball to throw 10 of them, plus four changeups, in 93 pitches. He threw it harder than he wanted – most came in around 80 miles per hour, and he feels it is most effective when he throws it 78 or slower. But it was good enough for him to gather confidence, to get closer to the happy medium Suzuki talked about.

“It carried over to the game a little bit,” Detwiler said. “It showed me more than anybody else: It’s good enough to play in a big league game.

“It’s gaining now. I threw a few good curveballs last night. And the game before, I threw good changeups. It’s building, building. But if it’s a key situation, I don’t want to get beat by my secondary pitches. I’m always going to second-guess myself after that: Why didn’t I throw my best stuff and make them hit it?”

Detwiler will remain a fastball-first pitcher, as well as a potentially dominant pitcher. Not many left-handers can throw like him – only five left-handed starters in  the majors average a harder fastball than his 92.7 mph. He is making a strong case to become the Nationals’ third starter in the postseason, in which case people would surely stop overlooking him and start talking about him.

“Ross is very talented,” Suzuki said. “You wouldn’t be surprised if you just see him take off, for sure. With his ability and his work ethic, and his willingness to learn, he’s going to be great.”