St. Patrick's Day drinkers of Guinness might be forgiven for thinking they've had a bit too much of the black stuff when they set eyes on the bar staff this weekend.
Pint pullers at selected Irish pubs around the world will be wearing specially designed green contact lenses advertising pints of Guinness, the drinks company said Thursday.
Guinness said it alighted on the subliminal campaign after research showed that more than half of British drinkers had not decided what to order by the time they reached the bar.
"We realized that there's still one place that drinkers have to look: into the eyes of the bar staff taking their order," said David Smith, brand director of Guinness GB.
Celebrations of St. Patrick's Day -- a highlight of the Irish calendar -- stretch from Dublin to New York this weekend, with drinking an integral part of the festivities.