Di Canio was pleased with the USA international's performance in defeat to Arsenal.
The Italian told the Sunderland Echo: "Now I need him to show that he can be one of the attractions in this league.
"He has fantastic potential but he has to transfer that potential into reality. You do that by working very, very hard in football, otherwise it is difficult.
"I know it is difficult - Jozy found it difficult in this division a few years ago when he was very young but he needs to use that experience as motivation to do better this time around.
"That should spark his desire and his ambition to prove that he wasn't just an average player in this league.
"He might think it was a case of wrong time, wrong team last time he was here and he can prove that by making a real success of his time at Sunderland.
"Now he is at the best place and if he trains hard and learns then he can do well."