Cape Verde have appealed to the Court of Arbitration for Sport (CAS) over the FIFA ruling which resulted in them being kicked out of the World Cup qualifying competition.
The Lausanne-based tribunal said on Tuesday it had registered the protest, although it could not yet give a date for the hearing and decision.
Cape Verde, who beat Tunisia 2-0 away to finish top of African Group B, forfeited the match after FIFA ruled that defender Fernando Varela had been ineligible to play.
Tunisia were awarded a 3-0 win which put them top of the group and into the playoff round in Cape Verde's place.
The Tunisians have already played the first leg of their playoff, drawing 0-0 at home to Cameroon last month.
Varela was banned for four matches after being sent off in an earlier Group B game against Equatorial Guinea, which Cape Verde lost 4-3.
That result itself was overturned, and the game awarded to Cape Verde 3-0, after FIFA ruled that Equatorial Guinea's Emilio Nsue, who scored a hat-trick, was not eligible to play.
Cape Verde argued that the red card and subsequent ban should not have counted as the match had been declared void.
Cape Verde appeal to CAS over World Cup expulsion