Royals shut down top pitching prospect Kyle Zimmer for at least six to eight weeks

On May 19, as he faced hitters in a game setting for the first time this year, Royals prospect Kyle Zimmer experienced a bout of tightness in his back. In his second inning of work, his fastball velocity dipped from the mid-90s to as low as 89 mph, a troubling sign for assistant general manager J.J. Picollo and the rest of the club’s developmental staff.

When Zimmer attempted to play catch the next day, his tightness remained. A day of treatment and rest did not alleviate the condition. Already marooned in extended spring training due to a bout of shoulder soreness this winter, Zimmer has now been shut down for six to eight weeks due to a strained latissimus dorsi muscle.

The muscle is located below the right shoulder, a precarious location for a pitcher. Even so, Picollo insisted the club conducted extensive examinations of Zimmer and ruled out damage to a ligament or a joint.

“Fortunately, it’s not elbow, it’s not shoulder,” Picollo said in a telephone interview on Tuesday morning. “These are the things I’m telling him. He’s obviously down right now, because he knows it’s another six to eight weeks of no activity.”

He added, “We’ve had so many different images on his shoulder. We know that his shoulder’s fine. So we’ve ruled that out. I hate to say: It’s just one of those things. It’s almost a mystery.”

An already troubling week for this franchise just got worse, with blemishes now marring their top best young pitchers. Yordano Ventura left his start on Monday night due to discomfort in his right elbow, and was scheduled for an MRI on Tuesday. Now Zimmer, the No. 5 pick in the 2012 draft, is dealing with yet another arm problem.

The injury also effectively rules out Zimmer contributing to the big-league club in 2014, a scenario the team hoped was possible. Once he picks up a baseball again in July, he will have to restart his entire throwing program. During that process, the team will assess the value and risk of attempting to build him up for this season.

“You do the math, and you’re running out of time,” Picollo said. “You’re running out of days. But I don’t want to rule it out, because we haven’t had those types of discussions just yet.”

Zimmer converted to pitching as a freshman at the University of San Francisco, and has experienced a series of injuries ever since. He underwent surgery to remove bone chips after the 2012 season. He hasn’t pitched in a regular-season game since last August, when the team elected to shut him down.

During the winter, he felt discomfort in his shoulder once again. The team doctors diagnosed him with biceps tendinitis. They tabulated a tentative 150 innings from him this season. His year was supposed to begin this week with Class AA Northwest Arkansas.

Instead, he will remain at the team’s complex in Surprise, Ariz. A big-league debut in September no longer looks likely, and a team searching for silver linings will have to look elsewhere.

To reach Andy McCullough, call 816-234-4370 or send email to rmccullough@kcstar.com. Follow him on Twitter at twitter.com/McCulloughStar.