Ghana coach Milovan Rajevac is facing a fresh injury crisis ahead of next month's African Cup of Nations after his key central defender John Mensah suffered a hamstring injury. The injury to the influential centre-back is also a worry for his club Sunderland ahead of their English Premier League trip to Blackburn on Monday.Mensah after the game at Ewood Park, limped out of Saturday's 1-1 home draw with Everton.Sunderland doctors have revealed that he damaged his hamstring after impressing in the game before he was substituted."We can all see that John Mensah is a really, really good player, but unfortunately he has hurt his hamstring again," Sunderland coach Steve Bruce remarked."We wish we could get him fit and able because we have made too many changes defensively."Doctors are hoping to get Mensah fit for Monday's game before he depart to South Africa for the pre-Nations Cup camping.If they are able to get him fit for the Premier League game, it will be a boost for the Black Stars ahead of the tournament in Angola.But if the injury persists it presents coach Milovan Rajevac with a new headache following injuries to captain Stephen Appiah and Laryea Kingston.There is still more hope that he can recover in time for the African Cup of Nations which is two weeks away.Source: Ghanasoccernet