On Wednesday, Kapler told SportsRadio 94WIP in Philadelphia that a limited Arrieta could be better than their other pitching options.
"He's having a harder time getting extended the way he normally does, especially on that curveball. This is limiting his ability to throw the ball where he wants to throw it," Kapler said. "All of that said, Jake is a competitor, and for the Phillies, it's always worth considering if Jake at 85 percent of himself is a better option than what we have at Triple-A."
Arrieta will start a game during the series against the Washington Nationals that begins Friday. Kapler told the radio station that how Arrieta feels pitching against the Nationals could play a role in determining the next step.
Following his last start Saturday, Arrieta had hinted that he lacked a feel for his pitches. He is 8-7 with a 4.67 ERA in 18 starts this year.
Arrieta underwent season-ending surgery for bone spurs in August 2011 while pitching for the Baltimore Orioles.
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