Daniel Nash, 40, was pulled over outside the boozer on June 4 around 7pm after a member of the public reported a black Ford Fiesta in the car park whose driver appeared “under the influence”.
Prosecutor Andrew Conboy said: “Police attended as he left the car park and he was stopped.”
Nash provided a sample of 82 micrograms of alcohol in 100 millilitres of breath at the police station.
Nash’s solicitor Lisa Tinsley said her client accepted he was over the limit.
She added: “He has had a stressful period and tells me his life had broken down.”
Nash, of Stanwood Drive, Walton, admitted drink driving.
A magistrate said he hoped the incident was an “isolated” one.
The defendant was handed a 20-month driving ban, a £300 fine, £85 court costs and a £34 victim surcharge.