The Black Cats boss feels that his side's clash with Mauricio Pochettino's men is a must-win game if the Wearsiders are to survive in the Premier League this season
The Black Cats are just three points clear of the Premier League relegation zone after drawing 1-1 with Stoke at the Stadium of Light on Monday night.
Sunderland have failed to build on Di Canio's bright start to his reign on Wearside but the Italian is adamant his side will have enough points to survive should they beat Southampton in Sunday's crunch fixture.
"The game at home to Southampton is now like a Champions League final," said the Italian boss.
"It's crucial for our destiny. We can stay up but we need to win another game. There is pressure on us for the Southampton game but if we win we should be OK.
"We have our destiny in our hands, we are still in a better position now than Newcastle and Norwich. If Wigan win tomorrow, they move to 38 points but we have a better goal difference.
"If we win our games our destiny is in our hands, it’s difficult. If Swansea lose tomorrow it may be because they are less motivated."
Sunderland came from behind to snatch a point in their clash against the Potters as John O’Shea scored a 63rd minute equaliser to cancel out Jon Walters’ early strike.
Di Canio believes that the point could be crucial come the end of the season, and lauded the spirit and determination of his side to respond despite being a man light following Craig Gardner's 34th minute dismissal.
"The way today’s point came it was vital for us," continued the 44-year-old. "I saw the fighting spirit that I wanted to see, the quality was there, I feel we deserved to get something more from the game.
"It was a massive point for us, the way it came it was massive. It wasn’t easy because after a few minutes we gave an easy goal away. This point will be crucial come the end of the season for sure.
"We went out in the second-half with more determination and desire, the fans in the Stadium were pushing the players on, it’s a magic combination."
The Italian admits he was disappointed to see Garner dismissed and has warned the midfielder, and his team-mates, they cannot afford any more moments of indiscipline like that in their remaining two games.
He added: "You saw what happened about Craig, it was a bad challenge. We have to be able to handle our aggression because I love Craig, his heart, passion and dedication.
"He’s an amazing professional but now we have to be careful because with two games to go we don’t have enough time to recover from our mistakes."