Madrid:Roger Federer is stunned by all the talk of match fixing and gambling in tennis and shocked that this might be happening.
"I've been around for the last 10 years and have never been approached or ever heard anything about it until these comments came out."
Andy Murray earlier said corruption in the game was common knowledge but later backtracked.
"Before I make any serious comments about this I'm going to speak with Andy," said Federer, who is in Madrid for next week's Masters tournament.
"I'm going to speak with the federation and all the bodies so I can get a better idea of just what exactly is going on with this right now."
ATP Player Council president Ivan Ljubicic and second-ranked Rafael Nadal have doubted Murray's claims.
Nikolay Davydenko, the player at the center of the sport's biggest match-fixing scandal, criticised Murray.
Davydenko withdrew from a match in Poland in August against 87th-ranked Martin Vassallo Arguello in the third set because of a foot injury. An on-line betting site, in an unprecedented move, then voided bets on the match.
The ATP has said it is investigating.
"I haven't read into the whole circumstances surrounding these stories, but I will be these days. I hope that this isn't happening. I think I would have heard something sooner if it had been", Federer said.