Shares in Mike Ashley's Sport Direct have fallen sharply after it delayed its results, citing uncertainty about trading at the House of Fraser chain it bought last year.
The company, whose results were due on Thursday, added its auditor, Grant Thornton, was facing increased scrutiny of its work for Sports Direct.
Sports Direct also indicated that it may not achieve its profits forecast.
The company's results may be delayed to 23 August.
Sports Direct said that other companies' audits were also taking longer.
In December, when Sports Direct published its half-year results, it said that, excluding House of Fraser, operating profits were expected to grow by between 5% and 15%.
But in its latest update, the company said: "There are a number of key areas to conclude on which could materially affect the guidance given in Sports Direct announcement of 13 December".
Around that time, Mr Ashley had described trading as "unbelievably bad".
News of the delay in Sports Direct's results sent its shares down more than 10% in early trading on Monday.
Mike Ashley owns huge swathes of the High Street. As well as buying House of Fraser for £90m - saying he wanted to turn it into the "Harrods of the High Street" - he has also bought Evans Cycles and owns several sportswear brands, as well as lingerie firm Agent Provocateur and luxury fashion chain Flannels.
Earlier this year, he had tried to have himself installed as chief executive of Debenhams, but instead had
his stake in the chain wiped out when the retailer was rescued by its lenders.
On Monday, Sports Direct also announced it was close to taking control of Game Digital.