Benfica management are excited about the early impact of Darwen Nunez.
Indeed, coach Jorge Jesus reckons the striker could be a bigger talent than former attacker Joao Felix, who left for Atletico Madrid a year ago for €120m.
Southampton failed with a bid for the former Almeria striker earlier this year, while Brighton and Sheffield United were also.
Jorge Jesus declared: "We got him. We must not forget that he is a child, he is 21 years old, there is a lot about the game that he does not yet know. He will learn with me and Benfica.
"All this decision-making ability, finishing and speed...
"He was Benfica's most expensive signing, and when there is no pandemic he will be the most expensive sale. He will be a world-class player."
Benfica coughed up €24m to bring Nunez to Portugal for the new season.