Arsenal have completed the signing of Germany international defender Shkodran Mustafi from Valencia.
Mustafi follows Lucas Perez, a £17.1m capture from Deportivo La Coruna, in moving to the Emirates Stadium and takes the Gunners' number of new summer arrivals to five.
Arsene Wenger said: "He is at the right age. He has good experience. He is a very focused player who can play with the ball as well. We have taken a great player but have prepared well for the future."
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According to Sky in Germany, the 24-year-old Mustafi has agreed a five-year deal at Arsenal, for a fee which could rise to £35m.
He will not link up with Arsenal until after the international break with Germany scheduled to play Finland and Norway on August 31 and September 4 respectively.
Wenger has been criticised for a perceived reluctance to spend money on new players in the current transfer window but defended his strategy and says there will be no further additions to his squad.
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"First of all we have a very big squad and we've spent a lot of money as well," he said. "We had to work very hard to get these two signings done.
"I expected it to last until Tuesday but fortunately it unlocked very quickly on Friday. We don't have any plans for anyone else now."