Per Mertesacker (born 29 September 1984) is a German professional footballer who plays as a centre back for Arsenal and the German national team. Mertesacker is a youth product of Hannover 96 and he made his senior league debut in November 2003. Mertesacker was soon dubbed "the Defence Pole" (die Abwehrlatte) by German tabloids and gained a reputation for his good disciplinary record and went 31 Bundesliga games without being booked.

Since joining Arsenal, their fans have nicknamed him the BFG, short for "Big Fucking German", but also alluding to Roald Dahl's The BFG due to his height. He is described as an imposing, reliable, dominant and an accomplished defender.