KAUNAS, Lithuania — The letter was short and to the point: A.S. Monaco, the elite soccer club on the French Riviera, wanted Ibrahima Sory Soumah to travel from his home in Guinea to France for a 10-day trial.

Soumah’s mind raced with the possibilities. If Soumah, a teenage midfielder, could succeed in the test period and convince his hosts of his value, he might take his place at one of the finest soccer finishing schools in the world, and maybe even follow the path that led George Weah, Thierry Henry and Kylian Mbappé from Monaco to global stardom. But even if he did not, Soumah knew that simply spending time under the tutelage of Monaco’s coaches would increase his chances of finding a different club and forging a decent pro career in Europe, fulfilling his dreams and those of his family back in Conakry.

Two years later, though, Soumah cuts a dejected figure. Trouble obtaining a visa meant he never made it to France for his trial in January 2017. So instead of Monte Carlo, the wiry Soumah, now 20, was recounting his story in the outdoor dining area of a kebab restaurant in Kaunas, Lithuania’s second-largest city. Here, signed to a contract that pays him a minimum-wage salary of $470 a month but, bizarrely, includes a multimillion-dollar buyout, he was sharing a bedroom with a teammate in a house owned by F.C. Stumbras, a club seemingly organized and run with the sole intention of flipping players for profit.

For hundreds of players around the world, this week is a critical one: a last chance to secure a move to one of Europe’s biggest clubs or leagues before the transfer window in most countries slams shut until January. To players like Soumah, praying fervently that he could find a way out well before the deadline, it is something else entirely.