O'Neill apologised for the timing of his departure five days before the start of the 2010-11 campaign after his side fought out a goalless draw with Villa on Saturday afternoon. But he is adamant he left Villa in a stronger position than when he took over in 2006.
When asked about the fans' reaction, O'Neill said: "I think it's a very natural reaction considering I've been gone two years and they've never known my reasons for leaving. It is very natural, I was expecting it and I got it."
He added: "With the idea that I left them in the lurch, I apologise maybe for leaving five days before the start of the season. But I came to this football club a fortnight before the season started with a team that had almost been relegated the previous year.
"The timing was not great five or six days before the start of the season but I think the team I left behind was infinitely better than the team I had started with.
"You had internationals galore and players who have gone to other clubs, James Milner, Ashley Young, Stewart Downing, and had great success.
"Listen, in the scheme of things it's a sideshow today and the main event is the two teams. It will always be that."
Villa boss Alex McLeish praised the fighting qualities of his young side, particularly as they had to cope with the loss of striker Gabriel Agbonlahor and defender James Collins through injury. Villa are now five points above the bottom three ahead of Tuesday's home clash with Bolton.
McLeish said: "Sunderland are a very good side with a lot of experience but the boys had the chances to win it with just a bit more quality in the final third of the pitch. They gave everything they could and the young boys are playing out of their skins.
"We have got four games to go and we have got to try and take points in every game. We are capable of that with the spirit the boys are showing."
Source: PA
Source: PA