Yabuta will become a free agent if his renegotiation with the Royals for a new major league contract fails before Nov. 16. He hopes to play back in Japan as well, according to baseball sources.
Yabuta signed a two-year $6 million contract, including a $4 million option for 2010, with the Royals in Nov. 2007.
He pitched for the Chiba Lotte Marines in Japan's Pacific League from 1996 to 2007 before filing for free agency.
Yabuta went 3-4 with a 7.14 ERA in 43 major league games.