Suspended Fifa vice-president Michel Platini will boycott an ethics committee hearing into allegations of corruption on Friday.
Lawyers for the Frenchman, who is also president of Uefa, believe the "verdict is already announced".
Both deny wrongdoing and were due to have personal hearings on Friday.
Blatter, 79, has compared the investigation against him to "the Inquisition", while 60-year-old Platini's attempt to lift his 90-day provisional ban from football denied by the Court of Arbitration for Sport on 11 December.
A verdict could come as early as 21 December, although both men could then submit further appeals.
Platini still hopes to be a candidate to replace the outgoing Blatter in the world football governing body's presidential election on 26 February - but can only stand if he is cleared.
However, he has expressed his "deepest outrage" at what he considers an attempt to prevent his candidacy.
In a statement issued on behalf of Fifa's ethics judges on Wednesday, Platini was told his case will be dealt with "independently and in an unbiased manner".
Platini's lawyer, Thibaud d'Ales, has previously said he believes Fifa's ethics investigators have recommended an "excessive" lifetime ban.
The Football Association said it would find it "difficult" to support Platini's bid to become Fifa president, even if he is cleared by the ethics committee.
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