Colback, who can also operate as a full-back, is currently considering a new contract with the Black Cats.
"Jack is in negotiations but I hope he is going to sign a new contract because it would be difficult for him to find a better club than Sunderland," Di Canio told Sky Sports News.
"I know Jack wasn't happy in general at the end of last year and I had a chat and told him I don't want unhappy people here, but he has a big chance this year."
According to Di Canio, Colback's best position is in defence and the manager believes that he is one of the best in the country.
"In my opinion Jack is one of the best few left-backs in the country. He has all the characteristic qualities - he is aggressive, tough and intelligent and he can push forward," he added.
Sunderland are back in Premier League action this weekend as they host Arsenal at the Stadium of Light on Saturday.