Arsenal manager Unai Emery says the club is looking to sign a central defender.
While the Gunners are working on a move for winger Nicholas Pepe, many believe their biggest weakness lies in defence.
Dani Ceballos has been brought in on loan from Real Madrid to replace Aaron Ramsey in midfield.
A move for William Saliba is one for the future, which means Emery must add to his squad if he wishes to compete with different defenders next term.
"We are deciding how we can improve," he said to the club's official website.
"At the beginning we were thinking to do one player to achieve the possibility to sign, but only if we can really, really improve this position.
"It's one centre back, one midfielder and one winger and we are going to [try] to do that.
"We are thinking the same. I want a team that is better than last year, so the players can achieve a lot being with us this season.
"Also we have a very good team. Only the players that can improve and help the squad [will be brought in]."
