Bernardo, Albion's Brazilian summer signing, saw plenty of that kind of talent when they were team-mates at Red Bull Leipzig and Red Bull Salzburg.
He told The Argus: "Keita for me is world class. I don't know if there is a better player than him at his age.
"He is (19) 95, like me. I cannot think of one player in the world that is better than him.
"He is a fantastic player without the ball, with the ball. He helped us (Red Bull Leipzig) a lot.
"He was at least 20 per cent of our team. It was actually a good team that finished in second place in Germany."