Jake Arrieta is an MRI away from having his season pronounced finished.
"I'll probably miss the remainder of the season," he said Wednesday.
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The right-hander will have an MRI on his aching elbow Thursday and is prepared to concede to season-ending surgery shortly after that.
"I wanted to try and make it work for as long as possible while I could remain effective and help the team," Arrieta said Wednesday. "After my start in San Francisco (Sunday), I realized that I'm not able to give the team what it needs. I'm confident and we're confident that we have options that can contribute to a further level than I was able to. The pain is something I can deal with, but it's the loss of feel and the ineffectiveness as the outings wear on."
Arrieta's departure puts Zach Eflin back in the starting rotation. He will pitch Saturday night against the Padres.
Arrieta has a bone spur in his elbow. He had surgery for a similar problem when he was with Baltimore in 2011. He came back healthy and won a Cy Young award with the Cubs in 2015.
He's older now - he will pitch at 34 next season - and that will certainly factor into things, but Arrieta believes he can come back and be effective next season. He is under contract for $20 million.
"Without this bone spur, I'm going to be able to use everything effectively," he said. "I've been doing this for a long time. I know what I need to do to execute certain pitches. I'm physically limited at this point. I don't have the ability to do those things. With some more space in the elbow, without that distraction in there, I'm going to be pretty good."
Arrieta lasted only three innings in his last start at San Francisco. He could not hold a three-run lead. The bone spur prevents him from throwing off-speed pitches with any effectiveness.
"I'm kind of cutting everything off, not really able to get fully extended, and that affects movement and command of those pitches," Arrieta said. "Going out there at this level with only a fastball that I can throw for strikes is not a really good spot to be in."
Arrieta first felt discomfort in the elbow in spring training. He admitted to the bone spur a month ago and said he wanted to pitch as long as he could help the team.
"I think we ran a really good process," manager Gabe Kapler said. "Specifically, we gave this a chance to work and every fifth day he, despite being uncomfortable and not being able to execute his pitches the way he wanted to, gave us everything he had. It was genuinely a heroic effort in a lot of ways.
"He wants the Phillies to be successful down the stretch and he realizes it might not be best for him to go out there and take the ball every fifth day, and we support that."
Arrieta signed a three-year, $75 million contract with the Phillies before the 2018 season. His $30 million salary for last season is the highest one-year salary ever for a Philadelphia athlete. (Bryce Harper's one-year salary will top out at $27.5 million over the next eight seasons.) In his two seasons with the Phillies, Arrieta has made 55 starts. He is 18-19 with a 4.26 ERA.
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