Both players are costly and in high demand though, and Boga in particular would be very expensive at €25m-plus.
And that has Vieira considering Lopes, 24, who he coached while in charge of Manchester City’s under-21s.
However, the twice-capped Portugal attacker has struggled for game time, making just five La Liga appearances.
Sevilla’s wing positions are occupied by Lucas Ocampos and Munir El-Haddadi, so a move may be in Lopes’ best interests.
And Nice are considering handing Lopes a platform to relaunch his career on the French Riviera.