The 44-year-old former Middlesbrough forward was dismissed on Saturday after his side were beaten 3-1 at home to Valenciennes.
"It hurts but that's life," Ravanelli told Canal Plus.
Club president Alain Orsoni added: "When things don't work, the only solution is a change of coach. Relegation would be a catastrophe. We're looking for a solution."
Ajaccio currently sit 19th in the Ligue 1 table with seven points from 12 games.