The FAI is investigating unusual betting patterns around a second game involving Limerick FC.
The Association is looking into Sligo Rovers' 6-2 FAI Cup victory over Limerick on August 24.
The FAI say it's "along similar lines" to their ongoing investigation into Limerick's 2-0 loss to Shelbourne last April.
Both investigations were launched following reports received from UEFA concerning unusual betting patterns around the two games.
An FAI spokesman said: “We have acted on the back of the UEFA report into two Limerick games, against Shelbourne in April and Sligo Rovers last month, and our investigations are ongoing.
Yesterday, gardaí took part in a search operation at a Limerick sports ground as part of an investigation into alleged match-fixing.
It's understood documentation and electronic devices were seized during the search.
UEFA also said it is aware of the reports and is awaiting further information on the matter.