Arroyo's spectacular outing was the antithesis of his previous relief outing, on March 4 against the Marlins, in which he allowed two runs in two innings.
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Even though he was able to mix things up against Houston, Arroyo, who signed a Minor League deal with Washington in January, still believes he has a lot to prove to himself and the Nationals. He wants to make sure he is strong enough to pitch every fifth day. Remember, he hasn't pitched in a Major League game since June 15, 2014, because of Tommy John surgery.
"I'm trying to build physically every day," Arroyo said. "My feel in my command is great. But you are trying to get to a point where you can throw four, five or six innings, come out and not feel like you have done so much damage to your body that you can't turn it around in four days. My goal here is to build up and continue to be the starting pitcher that is not throwing five innings and feeling like he is throwing 12 [innings]."
Arroyo is competing with Tanner Roark and Joe Ross for the final two spots in the rotation.
Bill Ladson is a reporter for MLB.com and writes an MLBlog, All Nats All the Time. He also can be
found on Twitter @WashingNats. This story was not subject to the approval of Major League Baseball or its clubs.