No soccer players had been implicated in the Spanish police investigation Operation Puerto, despite allusions from an International Cycling Union official that soccer and tennis players were being targeted along with cyclists, FIFA said.
FIFA president Sepp Blatter said Spanish authorities had confirmed in writing that no soccer players were part of the doping investigation.
"We're adamant that no footballers were involved," he said.
Leading cyclists Ivan Basso and Jan Ullrich were excluded from the Tour de France last week after their names turned up on a dozens-strong list compiled by Spanish investigators who led arrests and raids last month, seizing drugs and frozen blood thought to have been prepared for banned performance-enhancing transfusions.
Basso and Ullrich say they're innocent.
Jiri Dvorak, who heads FIFA's medical committee, said that he doubted blood doping was useful for soccer players at the World Cup because of the short turnaround between matches and because the risks far outweighed any minimal benefit.
Dvorak said there had been no positive doping cases from more than 200 tests so far at the World Cup.
Alexandre Guimaraes has resigned as Costa Rica's coach, saying he faced insults and physical threats since the "Ticos" lost all three of their games in the World Cup.
Guimaraes had signed a four-year contract extension before the World Cup, where his team was eliminated in the first round with three losses.
"I'm giving up that contract without any monetary benefit in return," Guimaraes said.
The Brazilian-born coach took responsibility for the bad World Cup campaign but said he will not tolerate personal attacks by some in the media who insist on "tarnishing my professional career."
"The criticism has become violent to the point that I've felt physically threatened, and if that violence is fueled by some in the media, it's even worse. This should not happen in Costa Rica," he added.
Irritate an Italian -- order a pizza. That was one German newspaper's recipe to upset Germany's World Cup semi-final rivals at kickoff time on Tuesday. The Taz daily printed a list of pizza emporiums spread across the country under the headline: "This is how we will annoy the Italians tonight: order pizza at 9pm."
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