Serbian head coach Ratomir Dujkovic, whose squad are on a tour of Italy, sent Lu back to China on Saturday after a heated clash with assistant Jia Xiuquan.
"Lu Zheng does not belong to our team any longer," Dujkovic told Titan Sports.
"He has been dismissed. It is unacceptable for any player not to respect the coaches. He is still young. Whether he can come back depends on his awareness of his fault."
The Olympic team, in Italy as part of their preparations for the Beijing Games next August, lost 4-0 to Juventus on Sunday following a 3-0 defeat to Inter Milan last week. They play Lecce on Wednesday.
