The latest allegations about corruption and bribery levelled at FIFA's hierarchy are explosive because they're the first from an insider -- a member of the football world governing body's powerful executive committee.
FIFA's investigation into presidential candidate Mohamed bin Hammam and CONCACAF chief Jack Warner was sparked by a report from Chuck Blazer, an outspoken 66-year-old American who is also a member of the executive committee.
Blazer's intervention comes a week before the FIFA presidential election in Zurich, where delegates from 208 countries will decide whether Sepp Blatter gets a fourth term or Bin Hammam a first.
Warner and Bin Hammam, the head of the Asian Football Confederation, strongly denied any wrongdoing.
Bin Hammam says he still expects to be able to stand in next Wednesday's election, suggesting the investigation is "little more than a tactic" from his rival.
But instead of spending the last few days of his campaign concentrating on his bid, the 62-year-old Qatari faces an appearance before FIFA's Ethics Committee on Sunday.