Ghana captain Asamoah Gyan is suffering from “a mild bout of malaria” and may not play against Senegal on Monday.
The Ghana Football Association said the striker was admitted to a hospital in Mongomo on Saturday evening and released on Sunday morning.
The disease was caught “at an early stage” and Gyan is said to be responding to treatment.
Senegal boss Alain Giresse must decide on the fitness of Sadio Mane, who has been out with a calf injury.
The Southampton forward was included in the squad despite his club’s insistence the player would not be fit.
Giresse said: “If he will not be able to play the first match, it will be the second if not the third. We’ll see the progress he will make.”
One big name missing from Senegal’s side is West Ham’s in-form striker Diafra Sakho, who has a back problem and is not part of squad. However, his Upton Park team-mate Cheikhou Kouyate will be lining up for the team.
“It was a dream for me to go to the Nations Cup,” he said. “Above all, there is my country and I put Senegal before (West Ham). With all the respect I have for my club, they respected my decision because I was not injured – it was a dream that no-one could mess up.”
The loss of Gyan would be a big blow to new Ghana coach Avram Grant, as the ex-Chelsea boss aims to extend the Black Stars’ unbeaten Cup of Nations record against Senegal.
But he will have Marseille forward Andre Ayew to call on, as well as Everton’s Christian Atsu and Mubarak Wakaso of Celtic.
- Ghana skipper Asamoah Gyan has had 51 shots across the last three Afcons; 19 more than any other player (Drogba 32).
- Counting both the African Cup of Nations and the World Cup, Gyan has scored in each of Ghana’s last seven major international tournaments, netting 12 goals in total
- Mubarak Wakaso was the joint-top scorer at Afcon 2013 with four goals (and one assist).
- From 2008 onwards, Ghana have only lost one of their 11 Afcon group matches (W8 D2), scoring in all 11 of these games
- The Black Stars have kept seven clean sheets in their last 10 group matches
- Senegal have gone 11 games without a clean sheet in this competition, though they have scored in nine of their last 10
- The Teranga Lions have failed to win their three previous Afcon games against Ghana (D1 L2)