Ned Yost became the Kansas City Royals' manager early last season, during Austin Jackson's rookie year.

During the many Tigers-Royals series he has managed since then, Yost has seen Jackson grow noticeably as a hitter.

"He used to be a guy that if you got ahead in the count, you knew you could bury him with sliders," Yost said. "That doesn't seem to me to be the case now.

"He's becoming a much tougher out than he used to be."