However, despite their contrasting fortunes, Mertesacker, who will win his 100th cap in Forteleza, has insisted that his team can't afford to be complacent against the Black Stars.
The 29-year-old told the Germany Football Association website: "I think African teams, in general, play very physically. They also have an incredible strength in one-on-one situations.
"I think that is part of their mentality. They are very dangerous so we have to play very, very clever tactically. We should try to avoid those one-on-one fights."
Victory for Germany would all but secure their place in the last 16.