Germany needed extra time to beat a determined Algeria side 2-1 in Porto Alegre, but Mertesacker insists that it did not matter how Joachim Low's side played as long as their place in the quarter-finals was secure.
"Would you rather we played beautiful football but got knocked out?" the Arsenal defender told ZDF Television.
"I don't know what you want from me - do you think that just Mickey Mouse teams are involved in the last 16? All that matters is we're in the quarter-finals."
Germany will take on France, who beat Nigeria 2-0 in Brasilia, in the quarter-finals this Friday.