The Germans need to get their South Africa campaign back on track after their shock defeat to Serbia and a loss to Ghana would mean a failure to qualify from the FIFA World Cup group stage for the first time in their history.
Low's side got off to the ideal start when they hammmered Australia 4-0 in their opening game, but after striker Miroslav Klose was sent off, the Serbs brought them down to earth with a 1-0 defeat.
Klose, the top scorer at the 2006 World Cup, is suspended for the Ghana clash at Johannesburg's Soccer City which will decide the winner of Group D and only a win will guarantee the Germans a place in the Round of 16.
Low expects a tough, physical encounter against Africa's Black Stars who are undefeated after a draw with Australia and a win over Serbia.
"Ghana are fast and can play well on the counter, they don't shy away from one-to-one duels as they are strong, they have players who can put in fantastic sprints," said the German coach.
"The general tempo against Ghana will be higher than Serbia, the Serbs were a bit slow out of the blocks and they had a draw in mind with only one forward.
"It will be quicker, but fitness is written with a capital 'F' in the Germany squad and we can cope with it."
Brazilian-born Cacau is expected to start as the lone striker with Lukas Podolski, who missed a penalty against Serbia, Mesut Oezil and Thomas Mueller as an attacking midfield.
Germany manager Oliver Bierhoff has said there will be no vendetta against Ghana midfielder Kevin-Prince Boateng, whose tackle on Michael Ballack in the FA Cup final ruled the German skipper out of the FIFA World Cup.