Gianni Paladini, 58, an Italian recently installed on the club's board, was attacked minutes before kick-off by a gang of five men as he walked towards his office in the Loftus Road stadium with a fellow director.
His assailants burst through double security doors, kicking him, beating him and demanding he resign his position as they held a gun to his head.
Fearing for his life, Mr Paladini signed his own "resignation letter" and broke free from the gang to the nearby boardroom from where he alerted police at about 3pm as his side's home game against Sheffield United was getting underway.
Armed police rushed to the ground where they made some arrests as well as in the nearby Uxbridge and South Africa roads. Mr Paladini was visibly distressed as he watched the second half of the club's 2-1 win and wept as he was escorted into the players' tunnel by two police officers after the game.
As Mr Paladini was recovering from his ordeal, in which he suffered suspected broken ribs, Scotland Yard detectives began to investigate the club's turbulent off-the-field recent history - which has seen an unseemly struggle for control of the once-fashionable west London club - for a possible motive for the attack.
From the heights of the 1970s, when their outstanding side boasted such stars as Gerry Francis and Stan Bowles, QPR sunk three divisions. After financial collapse under former owner Chris Wright, the club staved off closure with a £10m loan accruing £1m in interest per year.
Yesterday supporters were struggling to explain the attack, although some thought it may have been in connection with Mr Paladini's criticism of the club's finances.
The Italian, a former players' agent, bought a reported 22.1 per cent share in QPR for £600,000 in May last year. He openly questioned the £10m loan taken out by the club when it was on the point of folding in 2002. He told a recent fans' forum it was "absolutely imperative" to renegotiate the loan. The money was lent by ABC Corporation, registered in Panama, which has also lent £15m to Derby County.
Last autumn, Mr Paladini claimed the club was close to bankruptcy and, with the help of a football agent, Antonio Caliendo, organised a £1.7m investment into the club from two Monaco-based consortiums. The main shareholding in the club, thought to be 46 per cent, is held by his wife Olga.
Mr Paladini described the "petrifying" attack in an interview with the News of the World, saying he feared for the safety of his family. "I was petrified. One of them was holding my wrists and another was pointing a gun. They shouted at me to sign a piece of paper resigning from the board. Of course I signed it - but I have no intention of leaving the club.
"They tried to push me out of the ground but I managed to break clear and run into the boardroom, shouting for help. It was terrifying, I think they've broken one of my ribs. They were pushing me violently. I won't let them bully me out of the club. But they've taken my phone. I'm really, really frightened now for my family and friends but I won't let these cowards get away with this. This has brought shame to the club."
The audacious attack has astonished many long-standing fans. "I was at the game but I didn't realise what had happened until I got home," said Paul Finney from the QPR Loyal Supporters Association. "The fans are shocked because we really can't think that Gianni would have made enemies like that. It's also bizarre that a gang would want to do that sort of thing considering there must have been around 200 police at the ground."
Police are questioning the 11 men on suspicion of conspiracy to commit blackmail. A Met spokeswoman said: "Inquiries are continuing."