Ricardo Centurion's proposed move to Anzhi Makhachkala hangs in the balance with the Russian side keen to assess how the Racing forward recovers from ankle surgery.
It was understood both parties had agreed a deal which would see the starlet move to Eastern Europe in the summer.
However, it is now believed the Argentine club received an email from Anzhi stating the transfer is dependant on Centurion's reaction to surgery on his right-ankle, which will be operated on in the coming days.
The 20-year-old is set to be sidelined for at least three months, with Guus Hiddink's side reportedly reluctant to resume negotiations until the summer.
But with the Russian transfer window remaining open until Feburary 27, there is still time for another twist in the future of the Argentina Under-21 star.
Centurion is rated as one of the brightest young talents in South America and had courted the interest of some of Europe's leading clubs, including Italian giants AC Milan, prior to Anzhi emerging as the youngster's preferred destination.