“I had to go out there and prove to myself first that I belong here,” Detwiler said. “That was the first step. Now the next one is to prove that to everyone else.”

Detwiler concluded his promising spring training today by throwing five one-run innings, allowing five hits and no walks while striking out two Florida Marlins. He finished with a 2.65 ERA for the spring, his new mechanics having helped him put last year behind him. He reminded both himself and the Nationals why they used the sixth overall pick in 2007 to draft him.

“He’s really made a lot of strides,” Manager Jim Riggleman said. “Det’s never pitched himself off the club. He’s a big league pitcher.”

Detwiler pitched today, though, because the Nationals do not want the Marlins batting against a starter the Nationals will use in their early-season, intra-divisional meetings. Detwiler has pitched well, but he’s also known for some time he is ticketed to Class AAA Syracuse. He may not know it, but he’s likely to be the first pitcher called up when there is a need.

“There’s five spots and there’s six people,” Detwiler said. “I can do the math. It’s not a perfect game. Not everybody is going to finish the season as you’d like. I’ll get my opportunity when it comes.”

In the minors, Detwiler wants to improve the command the sharpness of his curveball. Just being back in the major leagues is not what Detwiler thinks about. He wants to be at his best, have all his pitches working, and he does not doubt that he can. “So you can get up there,” Detwiler said, “and be able to dominate.”