ENGLISH PREMIER LEAGUE:ASTON VILLA were thrown into turmoil yesterday after Martin O'Neill resigned as manager just five days before the new season starts.

Villa have refused to disclose any reasons behind the decision, which was confirmed in a statement yesterday afternoon, but the tipping point for O’Neill was when he learned he would not be able to reinvest the majority of the money generated from James Milner’s move to Manchester City.

Although O’Neill’s decision to end his four-year reign does not come as a great surprise – he admitted he was considering his future four months ago as his relationship with the chairman, Randy Lerner, began to unravel – the timing has come as a shock.

Villa play West Ham United on Saturday and unless Lerner can make a quick appointment, Kevin MacDonald, the reserve-team manager, will take charge in a caretaker capacity.

Perhaps of greatest concern to Lerner and Villa’s chief executive, Paul Faulkner, is there is no obvious candidate to fill O’Neill’s position. Mark Hughes would have been nailed on to get the job had he not taken over at Fulham a few weeks ago, and the Welshman must be cursing Martin Jol’s decision to remain at Ajax rather than move to Craven Cottage.

Jol has now been linked with the Villa position, while Bob Bradley, the USA coach, has also been touted.

How much money the new Villa manager has to spend will be of great interest given the manner of O’Neill’s departure. Lerner has invested €215 million since assuming control in 2006 – his arrival coinciding with the appointment of O’Neill – but he made it clear at the end of last season he was no longer willing to bankroll huge spending sprees.

Villa posted a record pre-tax loss of €55 million for the 2008-9 season as the wage bill during that period climbed to €85 million, up 42 per cent on the previous 12 months. Last season’s accounts are expected to be even worse.

O’Neill was told in January he would have to offload players to reduce the financial burden but only Craig Gardner was moved on.

Last Friday night, following the friendly against Valencia and with Milner’s transfer edging closer, O’Neill was asked how much he would be able to spend of the money that Villa received from City. He replied that he would “need to speak to the chairman and chief executive about that”.

The answer O’Neill subsequently received from Lerner and Faulkner appears to have convinced him he would be unable to make Villa a competitive force again next season, following three successive top-six finishes.

Villa’s players were completely unaware O’Neill was about to quit. The manager reported to Bodymoor Heath as normal yesterday and was out on the training field working with the squad in the morning. He gave no indication he was going to resign, leaving the players to find out when rumours began to spread and the odds on O’Neill being the first manager to leave his job this season started to tumble.

O’Neill was given far more control at Villa than many of his Premier League counterparts, although his replacement will not be allowed to operate from the same powerbase. Lerner and Faulkner, who has more responsibility since taking on the role of chief executive, have learned lessons after seeing a number of squad players pick up huge wages but rarely contribute.

Yet O’Neill can point to the signings of Milner and Ashley Young as success stories. Villa will more than double their money on Milner, whose transfer to City is expected to go through in the next few days with or without Stephen Ireland moving in the opposite direction.

Young would also command twice as much as the €11 million Villa paid for him.

Tottenham are considering tabling an offer as they seek to capitalise on yesterday’s events.

The Likely Lads Contenders for the Aston Villa job

Sven-Goran Eriksson– He was linked to the Fulham vacancy following his departure as Ivory Coast coach and is keen on a return to the Premier League.

Gareth Southgate– The former Villa defender has a good reputation in the game. However, Middlesbrough's relegation in 2009 blotted his copybook.

Martin Jol– The former Spurs boss was Fulham's first choice, but Ajax refused to play ball.

Slaven Bilic– He won many admirers during his four years in charge of Croatia. Is well thought of in England after spells as a player with West Ham and Everton.

Alan Curbishley– His failure to land another job following his resignation as West Ham manager in 2008 is something of a mystery given his success with the Hammers and in 15 years at Charlton.

Gianfranco Zola –Few players have been held in greater affection in the Premier League era. But question marks remain over his managerial abilities.

Bob Bradley– He has been increasingly linked with a move to England following an impressive four years in charge of USA.

Paul Lambert –Has impressed in the Football League, most recently by guiding Norwich to promotion to the Championship.