Travelling fans spent an estimated €11.5m here during the Six Nations Ireland-England rugby game in March, a new report shows.
The study, commissioned by Dublin Chamber of Commerce, found that an estimated 15,000 out-of-state visitors attended the match, which Ireland won.
Of the €11.5m spend, around half went to prepaid items such as hotels and restaurants, and around 15pc was spent on the ticket for the game itself.
Just under half was allocated to so-called out-of-pocket spending while in the city for the game.
The report estimated that the direct spend €11.5m added €21.3m to the economy.
Dublin Chamber of Commerce, which commissioned the study, said the findings show the value of hosting large sporting events to the economy.
"Big sporting events do wonders for the Irish brand and help put Dublin and Ireland in the shop window," said Dublin Chamber chief executive Gina Quinn.
"The country's hospitality sector relies on major events and a strong events programme is key to growing tourism numbers. The aim for Ireland should be to have a year-round schedule of events which will provide a regular flow of visitors from overseas.
"Such as schedule would include big sporting events, arts festivals, concerts and exhibitions."
Dublin Chamber has commissioned a series of surveys to be carried out at major sporting events and concerts over the course of this year. The first of these was carried out during the weekend of the Ireland/England Six Nations match in Aviva Stadium in March.
The study was carried out on the Chamber's behalf by UCD Michael Smurfit Graduate Business School. The report on the findings was compiled by Dr Paul Hanly, School of Business, National College of Ireland.
Other findings from the study shows that alcohol represented the largest out of pocket expense at €2.2m followed by €1.3m on food.