Police swept through the Italian national squad's training camp near Florence as part of a wide-ranging investigation into fixing that resulted in 14 arrests — including Lazio captain Stefano Mauri — to bring the total number arrested to about 50 since last year.
The Italian soccer federation later said Juventus coach Antonio Conte is under investigation for alleged wrongdoing while in charge of Siena in 2010-2011, and announced the withdrawal of defender Domenico Criscito from the Euro 2012 squad a day before the player lists have to be submitted to UEFA.
"He would have experienced a pressure that no human being can deal with," Italy coach Cesare Prandelli said of Criscito playing at the June 8 to July 1 tournament. "He wouldn't have been in the right frame of mind. And he could also have been called up by the prosecutors at any time, before a match.
"It was a peculiar day. My first reaction was one of fear: 'Oh my god, what can we do.' But then you have to find something positive out of this situation, such as if it had happened four days later it would have been a lot worse."
Two police cars arrived at the national team's training site at about 6:25am local time and left nearly three hours later. Criscito's house in Genoa was searched, while Conte's place in Turin was also raided.
Juventus president Andrea Agnelli said Conte would remain in charge and lent his support to Leonardo Bonucci, the Juve defender who is also reportedly under investigation but remains with Italy's squad.
Conte denied any wrongdoing.
"My story speaks clearly for itself," he said. "I've always showed moral integrity, honesty, fairness in every situation, whether as a player or a coach. I am completely innocent of any of this, as are my players.
"With Siena we won the (second-division) title with three games to go, thanks to a lot of sacrifice, sweat, tears and joy, with a group of extraordinary lads."
Siena president Massimo Mezzaroma is also under investigation, and Cremona prosecutor Roberto Di Martino said the club is at the centre of the investigation.
"There are seven, eight games being looked at and there have been statements that make us think they were manipulated," Di Martino said. "The searches involved players, coaches and directors of the club, including Conte and Mezzaroma."
Apart from those arrested Monday, three people have been placed under house arrest and two others are to present themselves to authorities. Five of the arrests were made in Hungary.
Former Italy striker Christian Vieri, who retired in 2009, is also among those under investigation, while Inter Milan's match against Lecce in 2001 is being examined.
"It's devastating news," said former Italy coach Giovanni Trapattoni, who is now in charge of Ireland. "If the authorities are acting it's because there's something there."
Mauri was arrested on suspicion of sporting fraud. Most of the footballers implicated now play in Serie B or lower leagues, although one, Omar Milanetto, spent five years at Genoa before joining Padova in 2011.
Numerous others have had their houses searched, including Chievo Verona striker Sergio Pellissier.
The investigation was started by judicial authorities in Cremona last year. It has resulted in former Atalanta captain Cristiano Doni being banned from football for three and a half years, and the arrest of former Lazio captain Giuseppe Signori.
Serie A clubs Atalanta, Novara and Siena were among the 22 Italian teams notified at the beginning of this month that they are being investigated by sports authorities.
Prosecutors in Cremona have detailed an extensive match-fixing ring stretching as far as Singapore and South America that was allegedly in operation for more than 10 years.
"It will be impossible to go right to the end with this because my office is not equipped to do so," Di Martino said. "If people wanted, we could go on forever but there is very few personnel.
"It will be impossible to go ahead with this for long."
Italy has only recently recovered from the 2006 match-fixing scandal — known as Calciopoli — that resulted in Juventus being relegated to Serie B for a season, plus points penalties for several other Serie A teams and lengthy bans for club and refereeing officials.
The Italian national team reacted in the best possible way, winning the World Cup later that year.
"This time it's worse than 2006. At least for me," Roma and Italy midfielder Daniele De Rossi said. "It's more shocking this time, with the police coming into Coverciano (Italy's training ground) and people I know being arrested.
"We're going to the Euros with a stain on us."