He said Mr Ashley paid only £1m and he wanted £14m damages.

Mr Ashley denied the claim and said Mr Blue was talking ''nonsense''.

Mr Justice Leggatt analysed evidence at a High Court trial in London earlier this month.

The judge heard that the dispute centred on a conversation in the Horse and Groom pub four years ago.

Ruling in Mr Ashley's favour today, the judge said no-one would have thought what was said in the pub was "serious".

Mr Ashley was not in court to hear the judge deliver his ruling, but his lawyers said he had won a "comprehensive" victory.

He said he had met Mr Blue and three other finance specialists at the pub and ''consumed a lot of alcohol''.

''I can't remember the details of the conversations that we had in the pub as it was a heavy night of drinking,'' Mr Ashley had said.

''I do remember that we had a lot of drinks and a lot of banter.

''If I did say to Mr Blue that I would pay him £15m if he could increase (Sports Direct's) share price to £8, it would be obvious to everyone, including Mr Blue, that I wasn't being serious.''

He said he paid Mr Blue, who he called ''Jeffers'', £1m for ''other deals'' unrelated to the night in the Horse and Groom.

Mr Blue told the judge that Mr Ashley was a ''serious businessman''.

He said the work ethic at Sports Direct was ''like nothing else I have ever seen''.

But he said Mr Ashley sometimes did business ''in unorthodox ways and in unusual venues''.

He told how Mr Ashley once vomited into a fireplace after a senior management meeting that was ''effectively a pub lock-in'' and said the businessman would take naps under tables at ''boring'' meetings.

Mr Justice Leggatt told lawyers, at the end of the trial, that the case had been ''a lot more interesting than some''.

In a statement issued after the ruling, Mr Ashley said: "The only reason the Sports Direct share price exceeded £8.00, and will hopefully do so again, is because of the sterling efforts of all the people who work at Sports Direct."