Jason Grey, posting about the AFL for ESPN, has this to say about Jeffress:

"Milwaukee's Jeremy Jeffress reportedly was just suffering from fatigue and not a health issue. Apparently, he just didn't recover from his previous side session very well, and had been moved up a day to get him on schedule to pitch in the Rising Stars showcase tomorrow, so that may have been part of it. For now, there appears to be no long-term concern, and he will be pitching again at the AFL."

Even if he was pushed up a day, he was still starting on four days rest. I wonder why he would've had trouble recovering from his last side session. Fire Ted Power?