Taking the place of left-hander Brian Matusz, who bunted a ball off his nose Tuesday, Arrieta threw seven innings of one-run ball, allowing seven hits and tying a career-high with nine strikeouts in the Orioles' 7-1 win over the Pirates Wednesday night at Camden Yards.
"He had better fastball command," Orioles manager Buck Showalter said. "Command the fastball and you can compete at this level, as long as you're not carrying around a dud. Jake realizes that. If you look at the numbers, they don't add up to the ERA. I thought one of the keys tonight was the ground ball back to him that he wasn't able to make the play on, and he didn't let the inning get away from him. That's been a challenge for him."
Arrieta was demoted to the bullpen after losing his sixth straight decision Friday against the Phillies, allowing a career-high 11 hits and career-high nine runs. He had allowed four or more runs in each of his last four starts.
But he took advantage of the opportunity to get back into the rotation on Wednesday. Showalter said he tapped Arrieta on the shoulder in the food room around 2:30 Wednesday afternoon and told him he would pitch.
"I can't do it in five days now, so that's a one-time pop," Showalter said, indicating that Arrieta would make another start when his turn comes on Monday at the Mets.
"He had a good outing tonight and I'm proud of him," Showalter added. "And he served a need we had with Brian, being cautious with him. His next turn in the rotation if he took it would be on [Monday]. I don't see why anything he did tonight [would] dictate that he wouldn't do that."