It looked as though Phil Bardsley's fine second half strike would be enough to secure Sunderland a maximum haul which would guarantee their Premier League status, but they had to settle for a point when Southampton substitute Jason Puncheon found a leveller.
Sunderland are four points clear of Wigan, who occupy the final relegation place, having played a game more with one left to play.
Di Canio accepts his side were not at their best in a contest that will not live long in the memory.
"It is a good point because obviously we didn't play a fantastic match," he told Sky Sports.
"Southampton did a better job than us so it's obvious at the end of the game it's a very important point.
"It's a crazy table with a lot of congested clubs on 41 points. We knew before that it was important to get the point we'll need to stay up."
Both sides were better after the interval and Sunderland's Italian tactician insists his methods are starting to have an impact on his side.
"In the second half our performance improved and that means our physical condition and desire is still there, which is important. In a few weeks you can't improve everything but it's important we keep believing in what we are doing to stay up.
"I knew before there was a fantastic passion here in this area. The environment in the club wasn't the same when I arrived here. I found a club under pressure to be honest."