Team officials said the Barcelona midfielder, runner-up in the recent African Footballer of the Year poll, has a knee complaint and sprained ankle and is battling against time to be ready for Tuesday’s Group D game against Guinea in Franceville.
Cheick Tidiane Diabate, the Girondins Bordeaux forward expected to be Giresse’s first choice in attack, has a hamstring injury likely to keep him out of the game.
Mahamane Traore, the midfielder from Ligue 2 club Metz, has still not recovered from a calf strain that limited his participation in the pre-tournament preparations.
Mali have already lost four players to injury ahead of the tournament.
French-based defenders Adama Coulibaly and Amadou Sidibe were ruled out of selection and both Mohamed Fofana and Khalilou Traore had to withdraw after being selected last week for the final 23-man squad.
Keita only recently returned from self-imposed exile from the Mali side after the last Nations Cup, persuaded back by Giresse after previously complaining of poor treatment by officials.
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