The race to win the right to host the 2016 Olympics has became increasingly bitter with Rio de Janeiro going on the offensive against bookmakers' favourites Chicago.
Rio, which is bidding to become the first South American city to host the Games, has lodged an official complaint with the International Olympic Committee's Ethics Commission about a remark made by Chicago Mayor which they took as a criticism of their bid, something that's not allowed under IOC rules.
Daley, reportedly said last week that hosting the World Cup, as Brazil will do in 2014, isn't the same as hosting the Olympics.
Rio believes that statement implies they're incapable of hosting the Games.
Ladbrokes betting agency have Chicago as outright favourite although the informed money is going on Rio.
While emotions are running high among the two front runners, third favourites Tokyo are denying any lack of emotion with several IOC members saying their presentations over the past year and a half have lacked passion.
Madrid is the fourth city bidding for the Games with a decision to be made by the IOC on Saturday.