Mertesacker ripped into the television reporter after Germany struggled to overcome Algeria in the World Cup on Monday night.
Joachim Löw's side needed extra time to finally beat the Algerian side 2:1 in Porto Alegre.
Asked by a reporter from broadcaster ZDF about the match, Mertesacker replied: “What do you want from me? What do you want so shortly after the game?"
He continued: “Do you think there are carnival troupes in the last 16 or what? They made it really hard for us for 120 minutes. We fought until the end and then came through, particularly in additional time. There were ups and downs.
“We were brave but we gave too much away.”
PHOTO GALLERY: Germany beat Algeria in World Cup