Shakhtar Donetsk have made an offer of around £12million for West Ham winger Luis Guilherme.
Guilherme, 18, has made just six appearances since joining from Brazilian club Palmeiras for £25m over the summer.
The Brazilian Under-20 international has amassed a grand total of 50 minutes across five Premier League cameos and a brief outing in the FA Cup.
He is tied down to the London Stadium on a five-year deal but his time in English football could be over by Monday.
He developed at Palmeiras as part of a potential golden generation of exports alongside Real Madrid's Endrick and Vitor Reis, who Manchester City have signed this window.