Last week Preston Council’s licensing committee turned down a similar application from the Ships and Giggles pub in the city.
But today councillors approved the Guild Hall’s bid to stay open late to show the boxing showdown live from Las Vegas this Bank Holiday weekend.
Police objected on the grounds that there could be large-scale disorder.
But Richard Simkin, head of operations at the Guild Hall, argued that the venue was used to holding major events and the 400-capacity night would be well managed with tight security.
The move will come as a blow to many other venues in Preston and elsewhere in Lancashire who have been told by police they will object to the late-night drinking.
Today’s decision could open the floodgates for more applications for the Saturday night event.
A Preston Council spokesman confirmed the application had been approved.