The Italian's short stint was brought to an end in September following a 3-0 defeat to West Brom that left the club with just one point from their opening five Premier League fixtures.
Sunderland have improved under replacement Gus Poyet, with the club reaching the semi-finals of the League Cup, while a 4-1 demolition of Fulham on Saturday lifted them off the bottom of the table and just point adrift of safety.
Bardsley - who had been frozen out under Di Canio - credits the upturn in fortune to Poyet, and is confident of beating the drop with the Uruguayan at the helm.
Speaking to The Shields Gazette, he said: "You've got to have a very good team spirit. I think that was beyond dead six months ago.
"Now we've dug it out. The manager came in and gave the players a new lease of life and everyone is taking their opportunity. That's what you need week in, week out, because there's decent competition at the club.
"When I came in, the team only had one point, but now we're on the way to getting out of it."
On the club's survival hopes, he added: "We believe we can do it . We're in our own mini-league and if we win on Saturday against Southampton, we're three points behind Hull in 10th.
"That's unbelievable when you look back three or four weeks ago. We need to just focus on ourselves and win as many games as possible."
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