Genk would sell their highly-rated midfielder Kevin De Bruyne to Chelsea for the right price, according to boss Mario Been.
De Bruyne has been a long-term target of Chelsea and over the summer the two clubs were known to be in talks about a possible deal.
But while the Premier League club managed to snare his former team-mate Thibaut Courtois, a deal to bring the Belgium international to Stamford Bridge failed to materialise.
Been, who was appointed as head coach at the end of August to succeed Frank Vercauteren, maintains he is well aware of the interest from the club he will face on Wednesday evening.
"I know that Kevin is a really great player and that Chelsea already talked about him," he said after his Chelsea counterpart Andre Villas-Boas reiterated his admiration for De Bruyne.
"Chelsea look and want to buy all the big talents so, for me, it wouldn't be a surprise if Kevin went to Chelsea. Everyone's got his price."
Genk captain Daniel Tozser is well aware of the capabilities of his team-mate and he has warned Chelsea may rue their inability not to conclude a deal for De Bruyne in the summer.
"I think every game is a chance for him to show himself," he added.
"Of course, he's a great talent. It's not surprising that Chelsea watched him. I hope personally he will show Chelsea tomorrow that they made a mistake in that he stayed with us."