Michel Platini appears before the Court of Arbitration for Sport on Friday to appeal his six-year FIFA ban for ethics violations, with his future in football hanging on the outcome.
The stakes could not be higher for the suspended head of European football.
A favourable verdict and the 60-year-old will take his place in the stands at the Stade de France for the Euro 2016 opener between hosts France and Romania on June 10.
A negative verdict will mean the former Juventus star barred from entering the national stadium, his glittering career in the sport having come to an ignominious end.
"This is the last avenue of appeal," Platini's lawyer Thibaud D'Ales conceded to AFP.
The Frenchman has been sanctioned over an infamous two million Swiss franc ($2 million, 1.8 million euro) payment he received in 2011 from then-FIFA president Sepp Blatter.
FIFA's ethics committee in December banned both men from all football activities for eight years. The suspensions were cut to six years in February.
Both men insist they did nothing wrong and that the payment was part of a legitimate oral contract tied to consulting work that Platini did for FIFA between 1999 and 2002.
The affair has already cost him a shot at becoming head of world football as he was forced to pull out of the race to become FIFA president in an election won by his number two at UEFA, Gianni Infantino.
UEFA has said it will not replace Platini until all his appeals are exhausted, so if the former French star is successful at CAS he could reclaim his job in time to preside over Euro 2016.
Platini's entourage is hoping for a decision "before May 3" when UEFA holds its congress in Budapest.
Blatter, who is due to testify at the hearing, has also appealed to CAS and is awaiting a date for his hearing.
Friday's Lausanne-based tribunal will get underway at 0700GMT.
It consists of three legal experts, one each representing Platini and FIFA and a president.
Platini has chosen Yale and Harvard educated Swedish lawyer Jan Paulsson, with world football's ruling body selecting Bernard Hanotiau of Switzerland.
The hearing will be chaired by Luigi Fumagalli, a University of Milan-educated Italian international law expert.
As part of his defence Platini's legal team will produce an invoice for the suspect payment in an attempt to prove there was nothing untoward about the transaction.
"Five people from the offices of FIFA were involved in this payment, which was processed by the Finance Committee and reported to the Executive Committee. It is far from a hidden payment," said D'Ales.
Platini's name has also emerged in the Panama Papers, a leaked set of 11.5 million documents that provide detailed information about more than 214,000 offshore companies listed by the Panamanian corporate service provider Mossack Fonseca.
But D'Ales denied this had any relevance to Friday's hearing.
"His fiscal situation was known by the Swiss authorities. This has nothing to do with it."