The financial world matched the disappointment of Manchester United's fans on hearing the news of Sir Alex Ferguson's departure.
The club's shares, which are listed on the New York Stock Exchange, fell by 3% immediately after they opened at around 2.30pm UK time and remained in negative territory for the close.
Investors were said to be worried by whether the club can appoint the right replacement for the most successful manager in English football history.
His successor will be the key figure at a business laden with almost £370m of debt and tightly controlled by its US majority owners, the Glazer family.
Shares in the club have surged 34% since floating in August at $14 (£9) per share, closing on Tuesday evening at $18.77 (£12.11).
The flotation allowed the Glazer family to sell 16.7m shares – equal to a 10% stake.
The Glazers bought the Premier League football club for £790m in 2005 in a controversial deal that enraged fans because they put in just £300m of their own money and loaded the club with debt.
The club's most recent annual results showed total revenues of £320.3m for the year to the end of June 2012, down 3.3% on a year earlier.
Dan Jones, a partner in Deloitte's Sports Business Group, said the club has been transformed under Sir Alex Ferguson from a financial point of view with revenue climbing by 14% on average.
"Manchester United is the top revenue generating club in England," he said. "For the 2011/12 season, United's revenue of £320m was £60m more than second-placed Chelsea. United's total wage bill of £162m was the third highest in English football for the 2011/12 season, behind that of Manchester City (£202m) and Chelsea (£173m).
"United's ratio of total wages to revenue of 50% remained amongst the lowest of all English clubs, thereby sustaining a level of annual operating profitability to help fund investment in facilities, youth development and playing talent.
"In world football, United's 2011/12 revenue of £320m ranked third in the Deloitte Football Money League, behind only Real Madrid and Barcelona who each currently benefit from having individual, rather than collective, broadcast deals."