Ghana are facing a severe blow in their quest to win their World Cup qualifiers next month as striker Asamoah Gyan suffered his fifth injury on Saturday night.The France-based forward is a major doubt for June's 2010 World Cup qualifiers against Mali and Sudan because of the thigh setback.Asamoah was replaced by Jires Ekoko in the first half clash with Lorient after feeling a pain behind his right thigh, a game which they won 3-1.Tests will be carried out on the striker on Monday to determine the extent of injury on what is suspected to be a hamstring injury.Even though Rennes have not stated his expected return date,a hamstring injury may take longer to heal thus making him a doubt for the World Cup away qualifier against Mali which is just two weeks ago.Gyan's latest setback is his fifth injury this season which has frustrated his club officials.His likely absence for the Black Stars must also hand a headache to coach Milovan Rajevac who is seeking to boost the striking options for the Black Stars.Junior Agogo could be invited to take his place at the unattached striker was left out of the Serbian coach's squad.Gyan joined the French club from Italian side Udinese for the club's recordtransfer fee at the start of the season.Source: ghanasoccernet