Manager Arsene Wenger says new signing Gabriel Paulista could be an important asset for Arsenal.
The 24-year-old joined the Gunners from Villareal for a reported fee of £11.2m and is in the squad to face Aston Villa on Sunday.
"What I saw was a great quality for a defender," the Arsenal boss said.
"[He has a] good level of concentration, he's physically able to adapt to the Premier League because he is quite a good size and he's quick as well.
"He has great commitment in the challenges and he's young. He's 24 years old and that's a good age for a central defender. He's ready to go - he'll be in the squad [for Sunday] certainly. He started training yesterday and he looks fit."
The 65-year-old does however believe that the Brazilian has to learn English so as to be able to communicate with the rest of the squad.
"You always need time to adapt, especially in a defensive position because you need to know your partners," Wenger says.
"At the moment he does not speak a word of English and that can cost you goals. If you mix going forwards with going backwards, it can cost you.
"It is a position where you need to know your partners and you need to communicate as well. We will try to teach him the important words. 'Offside' for example or 'Look at the linesman'!"
Striker Joel Campbell went in the opposite direction and the Frenchman says the 22-year-old will benefit from his six-month loan spell in the Spanish Liga.
"Joel has extended his contract so he will go to Villarreal and he needed games," Wenger explained.
"Here was a bit obstructed for him because there were too many players in the same position.
"After six months, he worked very hard every day and didn't get enough chances to play, so I wanted to give him a chance to continue to get experience at the top level."
