Sir Alex Ferguson's future as Manchester United manager has come under the microscope amid reports that the club's two largest shareholders want his contract negotiations halted.
John Magnier and JP McManus, who together own more than 25% of the club, allegedly plan to call an EGM if Ferguson is offered more than a 12-month extension to his deal.
Meanwhile United have launched an internal review of transfer dealings, while vowing that their policies are the "most rigorous in football".
Magnier, once a friend of Ferguson, fell out with the United manager over stud rights to the hugely successful racehorse Rock of Gibraltar.
Here, BBC Sport looks at the main players in the saga.
Status: Legendary gambler and major racehorse owner. Nicknamed the 'Sundance Kid.'
Famous for: Mighty punts in the betting ring and being universally known by his initials of JP.
Horses: Owns a string of top-quality National Hunt horses, notably the retired triple champion hurdler Istabraq. His current crop includes Baracouda and Flagship Uberalles. Ran a horse called Youlneverwalkalone in the 2003 Grand National.
Where he fits in: Fan of Arsenal, although his horses run in similar hoops to those of Glasgow Celtic, whose majority shareholder Dermot Desmond caddied for him when he played golf against none other than Tiger Woods.
Other connections: JP is friendly with Bahamas-based Joe Lewis, the former owner of Enic, which acquired big stakes in Glasgow Rangers and Tottenham Hotspur, along with Greek side AEK Athens.
Money: Said to be ranked 14th in Ireland's rich list. Bets in six-figure sums.
Status: Smartly-dressed horse breeding guru.
Famous for: Shrewd investments in the thoroughbred market.
Horses: Owns Coolmore, the leading stud in Europe, based in County Tipperary. Along with his wife Sue, has been a major shareholder in numerous Flat racing champions in recent years.
Where he fits in: Manchester United fan. John's wife Sue, the daughter of great trainer Vincent O'Brien, part-owned the 2001 Epsom and Irish Derby winner Galileo, and other leading horses. She shared ownership with former bookie and West Ham fan Michael Tabor, once linked with a Hammers buy-out.
Other connections: Magnier, along with McManus, were once reported to be interested in helping Dermot Desmond with his stake in Celtic. The current Celtic boss Martin O'Neill has been tipped as a future successor at Old Trafford when Ferguson eventually stands down or is forced out.
Money: With JP, initially held a 2.9% stake in United. Then acquired 8m shares on 12 July, 2001, the day Ferguson unveiled Juan Sebastian Veron as the country's most expensive footballer at £28.1m. A further 1.8m shares were bought 24 hours later.
The pair paid £62m for BSkyB's 9.9% stake in United and recently bought another 3.26m shares which takes their total holding in the club to 25.49%.
Sir Alex Ferguson
Status: Legendary football manager.
Famous for: Bringing European glory to Aberdeen and leading Manchester United to new heights, including an historic treble.
Horses: Owns several racehorses. Magnier said to have gifted him a half-share in the record-breaking Rock of Gibraltar, trained at the Ballydoyle stables owned by Magnier.
Their relationship flourished until 'The Rock' was retired and breeding rights were disputed.
Where he fits in: Has been racing with the men behind the Cubic Expression Company. Co-owned a horse called Juniper with Magnier's associate Michael Tabor, himself once linked with a takeover at West Ham.
Other connections: Friends with Portsmouth manager Harry Redknapp, the former West Ham boss and a fellow punter. Ferguson has taken his United players to the races at Chester.
Money: Ferguson is on a lucrative contract after a U-turn over his decision to stand down as manager, and is said to be close to signing a new deal that will keep him at the club until 2007 - unless Magnier successfully blocks the move.