Atletico Madrid are keen to sign Benfica forward Joao Felix but face stiff competition from other clubs, BBC Sport understands.
Felix, 19, whose contract has a 120m euros (£107.5m) release clause, recorded 15 goals and nine assists last season having made his debut in August.
A source close to the Spanish runners-up said it would be “very difficult” to sign the Portugal international.
Atletico require a leading forward with Antoine Griezmann set to leave.
The French international made the decision on his future in May, although he has yet to agree terms with another club.
Felix’s transfer would be the fifth most expensive in history behind Neymar (222m euros/£200m), Mbappe, Philippe Coutinho and Ousmane Dembele.
And he would become the second-most expensive teenager following the 180m euros paid to Monaco by Paris St-Germain for forward Kylian Mbappe in 2018.
Former Porto youth player Felix made his international debut against Switzerland in the Nations League semi-final earlier this month.
He scored a hat-trick against Eintracht Frankfurt in the Europa League in April, becoming the youngest Benfica player and the youngest Portuguese footballer to score three goals in Europe and the youngest player ever to do so in the competition.
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