"I've always had to compete to make a team since 2009," Karns said. "So it's the same story every camp for me. I've never been in a position where I was told, 'Hey, you've got a spot coming in.' For me, it's just another day at the office competing."
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Karns struggled a bit with his control in a 22-pitch first inning, allowing a single and walk, before breezing through a 10-pitch second. He said he was working strictly with has two-seam fastball and changeup in the first, but went to a full arsenal in the second that included his quality curve.
"I was definitely trying to work on something the first inning," Karns said. "In the second it was just go out there and play baseball."
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Karns said he needs to work more on pitching out of the stretch, which is usually the last thing that comes around for him. But otherwise, he was pleased with the day's work.
"The first time out, it's the accumulation of the whole offseason," Karns said. "You work out, you want to know, 'Did I do enough? Am I in good shape?' That was just first-time-out jitters. Once I settled in, I was doing just fine.
"I just have to work on that stretch and remember I'm working on things out here and not trying to pitch a perfect game every time out. I'm just trying to keep the ball moving and continue to improve."
After Karns was selected by the Nationals in the 2009 Draft out of Texas Tech, his professional career was delayed by shoulder surgery in 2010. He made his Major League debut with the Nats in '13, but he didn't earn a full-time rotation spot until last season with the Rays, when he went 7-5 with a 3.67 ERA in 27 games.
Karns has learned over the years to take things more in stride in spring.
"In the past, I'd be very critical of every little thing. And that just comes with lack of experience," he said. "Now that I'm a little experienced, I know this call isn't going to be made in a day or in the first week of camp.
"So I just need to continue to build, progress and do the best I can in the meantime. And have fun and get to know my teammates. Whatever happens, I respect their decisions and I'm going to go about my business as a professional."
Manager Scott Servais said Karns' initial control issues were understandable.
"He was amped up in the first inning and a lot of balls were up," Servais said. "He made a nice adjustment in the second and threw a few changeups and got the breaking ball going. Typical first time out there, no matter how long you've played. And he is a young player here competing, so it's not that surprising. But he made a good adjustment."