The Royals optioned Lynch to Triple-A Omaha on Wednesday.
Lynch had been making a strong case to open the season in Kansas City's rotation by posting a 2.77 ERA and 1.08 WHIP across 13 innings of spring ball. However, the 27-year-old left-hander will return to Omaha to begin the new campaign. Lynch allowed seven earned runs over 20 innings in Triple-A last season, and he could find himself back in Kansas City if he performs similarly in the minors.