Titus Bramble and Matt Kilgallon are out of contract and Phil Bardsley having done himself few favours after being photographed lying on the floor of a casino covered in £50 notes during a team night out.
The 44-year-old Italian was furious and players have been fined.
Di Canio has been less than impressed with the discipline at the club since his arrival at the end of March, and he revealed last week that he had handed out fines to seven players within a matter of days for breaches of the Black Cats' internal rules.
It has emerged in recent days that two of those fined have since turned to the Professional Footballers' Association for advice, sparking suggestions of a rift between the manager and some members of the squad.
However, Sunderland insist all the penalties are in line with the rules, which dictate that no player can be fined more than two weeks' wages.
Every offender has the right to seek independent counsel and sources insist it is not unusual for people hit with fines to seek advice from the PFA, which two have done on this occasion.