The Arsenal defender says Joachim Low's current squad is one of the strongest he has played in ahead of the World Cup final against Argentina on Sunday
Joachim Low's men qualified for this weekend's showpiece by seeing off Portugal, Ghana and USA in the group stages, before eliminating Algeria and France in the round of 16 and quarter-finals respectively.
Germany then humiliated Brazil 7-1 in the semi-finals to further confirm their status as the team to beat on Sunday and Mertesacker feels they are lucky to boast top-class players for every position.
"We have one of the strongest squads I've ever played in," the Arsenal defender told reporters.
"We have two excellent players for every position and everyone believes in each other.
"We have created excellent team-spirit during the tournament and with those magnificent players growing up together it makes it easier.
"It started off in 2009 when we won the Under-21 European Championship and beat England 4-0. I think there's a small link between these two tournaments
"The 2009 tournament was a real turning point. The youth academies started developing well over the last five or six years."
Germany last made it to the World Cup final in 2002 when they were beaten 2-0 by Brazil.