Club's goalkeeper had previously been approached by fixers
The Athlone Town goalkeeper involved in the team's controversial loss to Longford had admitted to being approached by figures connected to match-fixing at a previous team - but he did not engage with them.
Igors Labuts, a former youth international with Latvia, arrived in the midlands earlier this year as part of a new-look Athlone side.
He previously played with clubs in his native Latvia and Portugal.
Two of his former teams in Latvia, FC Jurmala and Ilukstes NSS, had been investigated over allegations of irregularities.
Labuts also played for Lisbon outfit Atletico CP, which was earlier investigated by authorities.
There is no suggestion of wrongdoing by the player.
The 26-year-old enjoyed a perfect start to his career in the SSE Airtricity League, keeping a clean sheet as underdogs Athlone beat Waterford FC, the hot favourites for the Division One title, 1-0.
However, the club is now firmly in the international spotlight in the wake of Saturday's 3-1 loss away to Longford.
The FAI was contacted by Uefa in response to suspicious betting patterns while the game was in play.
It is understood that an FAI investigation will look specifically at the large number of bets placed, late on in the game, predicting that Athlone - who were then losing 2-1 - would concede a third goal.
The FAI will speak to players and staff at Athlone next week as part of its inquiry.
The goalkeeper previously told a Latvian newspaper that he was "shocked" when he saw his name mentioned in Portugal.
"I know that I am clean, but it's unpleasant and my reputation has been damaged," he said. "It's hard to say why, but it's probably due to my past."
He also confirmed he had been approached by unnamed figures connected to match-fixing. He added that he did not engage with the individuals whatsoever.
"There has been something, but I did not want to deal with it, I want to play football and progress as a goalkeeper," he said.