Former Aston Villa chairman Doug Ellis has urged fans to get behind owner Randy Lerner.
Ellis believes the timing of Martin O'Neill's decision, just five days before the Premier League campaign, is far from ideal.
He told Sky Sports News: "I was not entirely surprised by Martin's resignation although I was disappointed by the timing of it.
"I'm saddened. I think the supporters will be saddened - on the whole.
"Martin has done a very good job for Villa and I'm glad I appointed him.
"It is just a pity it has been done at this particular time."
Ellis, who is now a life president at Villa, has faith in Lerner to find the right replacement for O'Neill, who replaced David O'Leary in the summer of 2006.
Ellis said: "Never forget the club is bigger than any one man, whoever it is.
"The club will continue and, in Randy Lerner, Aston Villa have a very good chairman (owner).
"I'm delighted I chose him in comparison to the four other predators who were trying to buy the club.
"I know that Randy Lerner will find a successor and I hope all the supporters will back him and chief executive Paul Faulkner in finding the best possible man for the job."
