A licensee couple have been successful in the High Court in getting a major reduction in the amount of rent being sought by their landlord, Enterprise Inns.
Anti-tie campaigners are claiming it gives hope to other tied tenants seeking rent reviews.
Charles and Leslie Brooker, licensees of the White Horse, in Hambrook, near Bristol, should now pay £18,000 rent, instead of the £30,800 wanted by Enterprise, after the ruling on their lease renewal this week.
In his judgement, Judge Hughes QC said his assessment was based on rent being 35 per cent of the divisible balance of £51,500, instead of the norm of 50 per cent.
He said this would be seen as a "sensible compromise" in the current "highly unusual circumstances" adding that trading conditions facing pubs are "much worse than anyone can remember".
The judge said his decision was based on the "long term decline in beer sales".
However he identified other factors currently affecting the market, including "the unprecedented economic crisis"; the lack of availability of capital; the "market-depressing" effect of the news of pub closures and the smoking ban.
Judge Hughes also highlighted that the hypothetical tenant - the legal model used to assess fair rent - would be able to make a "much greater profit" buying beer on the open market, but this was partly counterbalanced by free accommodation for tenants, he said.
But he criticised Enterprise's lawyer for suggesting the unemployed, "with their redundancy payments, might step into the void created by the credit crunch".
Robert May, Enterprise's national rent controller, admitted though that "the days of the enthusiastic amateur publican were over".
Campaign group Fair Pint said the ruling gives hope to all tenants facing rent reviews.
The group's David Morgan, a chartered surveyor who gave evidence at the case said: "This will give some hope to all those tenants facing rent reviews now where pub owners are still trying to get increases.
"This is commonsense law and we need more of that in the pub sector, rather than pubco surveyors making it up as they see fit."