Chinese club Shanghai Shenhua will take its battle against star striker Didier Drogba's move to Turkish side Galatasaray to football's governing body FIFA this week, domestic reports said on Monday.
The Ivory Coast striker left the club in acrimonious circumstances last month, with Shanghai saying he had breached his contract.
"We now have evidence which we believe will give Shenhua a 99 per cent chance of winning a lawsuit at FIFA," a lawyer acting for the club told the Sina web portal.
The anonymous source from "Shenhua's legal team" said papers would be submitted to the sport's governing body on Wednesday.
The report said Shenhua will provide evidence that Drogba breached his contract and that Galatasaray had violated FIFA rules by luring a player away from his current club.
Shenhua declined to comment when contacted by AFP.
Chinese media previously reported Drogba had asked FIFA to nullify his contract after the club defaulted on payments following a shareholder dispute dating back to September.
Drogba came off the bench to score five minutes into his Galatasaray debut on Friday, a 2-1 victory over the Turkish league's bottom club Akhisar.
The striker signed an 18-month, 10 million euro ($13.5 million) deal with the Istanbul side, who are due to play German side Schalke 04 on Wednesday in the last 16 of the Champions League.
Drogba -- a Champions League winner with English Premier League side Chelsea last season -- had signed a two-and-a-half year deal with Shanghai in June last year on a reported salary of $300,000 a week.
Drogba's exit from Shanghai followed that of former Chelsea teammate French striker Nicolas Anelka, who joined Italian giants Juventus on loan.