Japan star Atsuto Uchida's decision to fly home and undergo surgery in his native country for a knee injury has put the defender offside with his Bundesliga club.

The 27-year-old, who has made 74 appearances for Japan, has not played for Schalke since their stunning 4-3 win at Real Madrid in the Champions League last 16 clash in March when they bowed out on aggregate.

He opted for surgery on the patella problem against the advice of both the team doctor and Munich-based expert Hans-Wilhelm Mueller-Wohlfahrt, who treats the German team.

"Atsuto Uchida has flown to Japan and has undergone an operation due to ongoing patella tendon problems. Our doctors' advice was different," Schalke's director of sport Horst Heldt told schalke04.de tersely.

"We were convinced that it made more sense to take on a conservative approach to treating the injury.

"That was an opinion also shared by Germany national team doctor Dr. Mueller-Wohlfahrt, who Uchida visited a number of times.

"However, the player made a different decision. He has the right to choose whichever doctor he wishes."

With the new season set to start in Germany on August 14, Uchida is set to miss the start of pre-season training next month.

"We will see how the first six weeks of Uchida's rehab in Japan go and expect him to return to Germany after that," said Horst.

Schalke are without a coach after Roberto di Matteo resigned last month and Uchida will have a new boss on his return to the Gelsenkirchen-based club.

Both Augsburg boss Markus Weinzierl and Belgium national team coach Marc Wilmots have been linked to the vacancy by the German media.