As reported in later editions of yesterday's Evening Times, news of the investigation came as four other people were arrested yesterday in an early morning police raid in Italy.
It was reported that Cremona prosecutor Roberto Di Martino, who has been leading the operation for three years, confirmed that Gattuso, 35, and retired Lazio player Cristian Brocchi allegedly were part of a ring that fixed Serie A and other Italian matches at the end of the 2010-11 season.
Former AC Milan and Italian World Cup winner Gattuso - whose real name is Gennaro - reportedly had his home searched as part of the investigation.
Gattuso's agent Andrea D'Amico said: "Gennaro is stunned by the news. I spoke to him and he is returning home (to Milan).
"We are remaining calm and we have to be patient and see how the investigation develops.
"However, just because he is under investigation does not mean anything, for all we know this could be just false allegations.
"Sometimes when you are a famous player, it is very easy for your name to appear and to be a target. We will wait and see how the situation develops."
Reports claim that Gattuso and Brocchi both had telephone contact with people that were arrested on Monday night by police.
The four taken into custody are charged with sporting fraud as part of 'Last Bet' operation, an investigation that began in 2010 and that has already led to 54 arrests, including current and former Italian players.
Gattuso played for Rangers in the late 1990s.