Shakhtar Donetsk manager Mircea Lucescu today told Chelsea that Willian is theirs for the right price.
The Brazil international has shone for the Ukrainian giants since joining from Corinthians in 2007, picking up three Premier League winners' medals and the 2009 UEFA Cup during his time at the club.
Such form has attracted the interest of European giants such as Chelsea, who Shakhtar chief executive officer Sergei Palkin revealed in January had seen a £16.7million bid for the attacking midfielder rejected.
The club insisted Willian was not for sale at the time, but boss Lucescu today changed tack.
"They have to pay the price," he said at the club's training centre on the outskirts of Donetsk.
"They have to pay the price because we bring the players here at 17 or 18 years old.
"We pay a lot of money because they are talented players and we bring them up. I have 23 or 24 [players like that], not only Willian.
"Luiz Adriano, Douglas Costa, Alex Teixeira, Dentinho, Alan Patrick - they are very young and they are already prepared to win the championship with a good mentality.
"They have played a lot of matches in Europe and they have a very, very good value.
"If Chelsea pay his [asking price], I am not against letting my players play for the big clubs.
"If they pay the price, he can go. If not, he will remain here because he has another two-and-a-half years on his contract."
Lucescu is unsure whether Chelsea will make a renewed bid for Willian in the summer, but believes his departure would not have a massive negative impact on the squad.
"It is not my problem," the Romanian said of the transfer fee. "It is the problem of our club and Chelsea.
"But if Chelsea want to take good players that are very well educated then at Shakhtar we have a lot of Brazilians.
"It is not only the performances they have done here but their education, which is very, very important.
"For us, every transfer is very difficult because we taken a player of 18 years without a European education."
Chelsea are in the headlines across the world today after defeating Barcelona in their Champions League semi-final first leg at Stamford Bridge.
Shakhtar defender Tomas Hubschman watched the match and was impressed by Czech Republic team-mate Petr Cech.
"He played the best and is the reason Chelsea won yesterday," he said of the Blues goalkeeper.
"I am not a supporter of Chelsea but their goalkeeper is a friend of mine so that is why I watched.
"As for me, I like Barcelona. I prefer them more because they play very good and beautiful football. Chelsea play for the result, to win."