Arsenal manager Arsene Wenger says he added defender Shkodran Mustafi to his squad because of lack of depth in the defensive department but also because of his experience.
The 24-year-old has already featured in the Italian Serie A, Spanish Liga and the English Premier League.
He will add depth to a department which lost Per Mertesacker, Gabriel Paulista and Calum Chambers this summer.
The Gunners paid £35million for the Germany international who signed a five-year contract with the club.
"We needed a centre back because of the long-term injuries we have," Wenger told Arsenal Player.
"He has already played in Italy, he has already played in Spain and he has played with the German national team.
"He is a very intelligent boy, that was important in my decision as well. He is very focused as I told you, and he knows the rigorous climate of the Premier League and how much you have to fight for every game.
"I know as well he is a very focused player who can play with the ball as well. That is important for us, and all this quality made me decide to try and get him.
"The player wanted to join us as well, and I think he will hopefully be happy here and will enforce our squad. It puts us in a good position."