Martin O'Neill has resigned as Aston Villa FC manager five days before the new English Premier League season begins and just over a week before they enter the UEFA Europa League.

Villa announced the 58-year-old's unexpected departure in a statement on Monday afternoon, appointing reserve-team manager Kevin MacDonald as caretaker ahead of Saturday's opening fixture against West Ham United FC and their UEFA Europa League play-off with SK Rapid Wien on 19 and 26 August. O'Neill said: "I have enjoyed my time at Aston Villa immensely. It's obviously a wrench to be leaving such a magnificent club."

Former Northern Irish international O'Neill, who won the European Champion Clubs' Cup twice as a player with Nottingham Forest FC, spent four seasons at the Villa helm, guiding the club to sixth place in each of the last three years as well as the 2010 League Cup final. He had previously been in charge of Celtic FC, and has worked in management since 1987.