Sunderland forward Stephane Sessegnon will miss the rest of the season after failing in his appeal against the three-match ban for his sending off against Aston Villa on Monday night, the FA has confirmed.
Referee Lee Probert issued a straight red card for Sessegnon's second-half challenge on Yacouba Sylla as the Black Cats slumped to a 6-1 Barclays Premier League defeat.
The player was astonished to be dismissed and Di Canio signalled the club's intention to appeal within minutes of the final whistle, but that has been rejected.
An FA statement read: "At an Independent Regulatory Commission hearing today, Stephane Sessegnon's claim of wrongful dismissal was unsuccessful meaning the Sunderland AFC player's three-match ban remains with immediate effect.
"Sessegnon was dismissed for serious foul play during his side's game against Aston Villa on Monday 29 April 2013."
The Benin international's red card was the second of his career in England, the first coming in a 1-1 league draw at Newcastle in March last year.
Sessegnon's absence will come as a major blow as he has been in sparkling form under new boss Di Canio, scoring the first goal in their 3-0 derby win at Newcastle and then firing his side to victory over Everton six days later to send them clear of the relegation zone.
Despite their humiliation at Villa, Sunderland, like Paul Lambert's men and the Magpies, remain five points better off than 18th-placed Wigan, although the Latics have a game in hand.
Sunderland take on the Potters and Southampton at home in their next two games and will hope to have safety wrapped up before travelling to White Hart Lane on the final day to face a Tottenham side which could still be battling for a Champions League place.