Report: K.C. Royals starter James Shields passed kidney stone

Kansas City Royals pitcher James Shields was given a long layoff between starts in part because he was passing a kidney stone, he told The Kansas City Star.

The team elected to start Jason Vargas instead of Shields in game 4 of its American League Championship Series against the Baltimore Orioles. 

Shields told the paper that he was dealing with "excruciating pain" and that he "wasn't feeling good."

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The right-hander is scheduled to start Game 1 of the World Series against the San Francisco Giants on Tuesday. 

“I probably could have used the extra day (of rest),” Shields said. “But I just told them ‘Whenever you need me, I’m ready to go.’”

Shields has yielded fewer than four earned runs only once over his three starts this postseason and has pitched a total of 16 innings.

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- Chris Johnson