Annan was withdrawn in the last minutes of his side’s Premier League game away at Berekum Chelsea on Sunday due to an injury.
Annan was involved in a collision with a teammate and a Chelsea player rendering him incapable of continuing the match.
He was replaced by compatriot Kwame Baah for the closing stages of the match.
Annan who reported to Kotoko’s Adako Jachie Training Complex this morning.
But did not train underwent a scan to ascertain his situation.
Initial reports reaching FMiG indicate the goalkeeper won’t be able to recover in time for the CAF Champions League clash which takes place on Friday November 27.
The Porcupine Warriors travel to Mauritania for the first leg and will have to play without their captain.