Portuguese FA technical chief Pauleta believes Joao Felix could star for Atletico Madrid in the Champions League run.
Atletico face RB Leipzig in their quarterfinal next week in Lisbon.
On Felix, Pauleta said, "I think this Champions League is different.
"The eight clubs will think that it could be an opportunity, since anything can happen in a game. And all the clubs and players see it as an opportunity.
"It is time for the players who make the difference [to step up]."