Graham Calvert also sought personal injury damages

Greyhound trainer Graham Calvert, 28, of Houghton-le-Spring, near Sunderland, said the company failed in its "duty of care" and the judge agreed.

But Mr Justice Briggs ruled on Wednesday that William Hill was not liable for the losses.

He ordered Mr Calvert to pay £175,000 interim costs to the firm, but the payment is on hold pending an appeal.

The judge said he would only pay 80% of the estimated £420,000 bookmakers costs after the late disclosure of key evidence.

He ruled that although the company failed to take "reasonable steps" to stop Mr Calvert from telephone gambling, Mr Calvert's "pathological gambling" would still probably have led to his financial ruin.

In summary of his ruling the judge said: "William Hill's failure to take reasonable care to exclude him from telephone gambling... did not therefore cause Mr Calvert any measurable financial or other loss."

New accounts

Mr Calvert had also sought further compensation after he claimed he had not only lost money but also his wife, health and livelihood.

William Hill was accused of manipulating his gambling disorder to gain as much revenue as possible by letting him place bets after asking it to close his account under a self-exclusion scheme.

It was alleged the bookmaker allowed Mr Calvert to open two new accounts and to make bets totalling about £3.5m between June and December 2006. During this period he lost a total of £2.1m.

The company denied any wrongdoing and said it could not be held legally liable for Mr Calvert's losses.

David Hood, spokesman for William Hill, said: "We stated from the outset that there was no case to answer to Mr Calvert.

"The judge found that no general duty of care is owed to problem gamblers and that Hills handling of Mr Calvert's calls did not cause his loss."

National database

The judge granted permission to appeal against the ruling and Mr Calvert has until 16 April to lodge an appeal.

Ward Hadaway, the law firm representing Mr Calvert, said: "It is particularly disappointing that the judge decided not to award our client any damages because he was so critical of William Hill.

"The criticism was of the way in which they dealt with our client and of their self-exclusion procedures generally.

"He found that William Hill had failed Mr Calvert in a number of different ways.

"The judgment highlighted the need for a national database allowing problem gamblers to self-exclude from all bookmakers in one go."