Yokohama F. Marinos defender Naoki Matsuda on Friday ruled himself out of Japan's upcoming friendlies in Africa and Europe because of a sore back.
The 26-year-old, who has had a long-term back problem called spondylolysis, a stress fracture or defect in a vertebra, complained of back pain on Thursday evening and was unable to train with Yokohama on Friday.
Japan coach Zico on Monday named Matsuda to the squad that will play Tunisia next Wednesday and Romania in Bucharest three days later.