De Gea has begun to silence his doubters since the New Year.
But Kuszczak says: "I do not know whether he is a good enough goalkeeper for such great team as Man Utd.
"He is still a young player, he has to learn a lot and has not developed such skills like club legends Edwin van der Sar or Peter Schmeichel.
"But he has huge support from the coaching staff, which should help him a lot. He got a chance and now he has his future in his own hands."
- with Dariusz Kurowski