Manchester United boss Sir Alex Ferguson is coy over his interest in Athletic Bilbao's young stars.
Javi Martinez, Fernando Amorebieta, Fernando Llorente and Iker Muniain are all interesting Premier League clubs - including United.
"There are several players in this present Bilbao team who are going to do well," Ferguson said.
"They are young and you can see there is progress in them.
"Life is life. When players do well, they maybe want to move or bigger clubs want to come for them.
"It is difficult to say how a club like Bilbao deals with that situation."