Rajevac optimisitic over Essien
Chelsea midfielder Essien, who came on as a half-time substitute in Friday's 3-1 defeat by Ivory Coast, only joined the squad on Wednesday after bad weather delayed his departure from London.
"Essien came in only two days ago and he was injured," Rajevac told a news conference, referring to the hamstring problem that had kept the Chelsea player out for more than a month.
"He was not ready to play 90 minutes, he was actually not really ready to play 45 minutes. It was a big risk.
"We have three rest days so we hope he will be ready to start against Burkina Faso."
Ghana are bottom of Group B with no points. Burkina Faso are second on one point and Ivory Coast have qualified for the last eight with four points from two games.
The group is a three-team affair after Togo left the competition in the wake of a deadly gun attack on their team bus last week.