The Comoros were forced to name an outfield player in goal for their historic Africa Cup of Nations last-16 tie against hosts Cameroon on Monday with two goalkeepers ruled out due to Covid-19 and another missing due to injury.
Fullback Chaker Alhadhur was therefore named as the starting goalkeeper as the tiny Indian Ocean island nation play their first ever Afcon knockout tie.
The Comoros tried to get clearance for goalkeeper Ali Ahamada to play in the game after he provided a negative test, but the Confederation of African Football (CAF) ruled him to be ineligible as he tested positive just two days before the tie.
Ahamada's fellow goalkeeper Moyadh Ousseini has also been ruled out with Covid after the virus swept through the squad, while Salim Ben Boina is injured.
In a letter sent to the Comoros Football Federation and seen by AFP, CAF doctor Sidiki Boubakary wrote that Ahamada's "first positive test was recorded two days ago".
He added: "He could have been eligible had the first PCR test dated from five days ago or more. As a result...Ali Ahamada is not eligible to play in the match."
CAF's protocol on PCR test results for the tournament was sent to teams in October.
The Comoros put in a request to CAF for Ahamada to be given an exemption to play in the game, given that they had no other goalkeeper available.
The 30-year-old Ahamada flew from Garoua, where he had been isolating after their last group game against Ghana, to Yaounde on Monday afternoon in the hope of being able to play, according to a source close to the Comoros delegation.