Four ways that Unai Emery can improve Arsenal's defence

#3 Swapping Bernd Leno for Petr Cech

Leno, pictured here on the substitutes' bench against Cardiff, is yet to make his senior debut for Arsenal

Everyone had their reservations when Bayer Leverkusen's first-choice goalkeeper Bernd Leno join Arsenal this summer for £20m. After four league games though, it's certainly time the Germany international starts ahead of his more experienced teammate.

So far, going by expected goals (xG), the Gunners should have conceded five goals based on the quality of goalscoring chances they have conceded. Cech has let in eight - including very savable long-range efforts from Raheem Sterling and Marko Arnautovic.

In addition, his distribution out from the back has placed his teammates under unnecessary pressure on regular occasions, providing opponents with added hope they can fashion chances too. For every long ball he's completed this season, he has misplaced two more. Leno, who is known for his excellent distribution ability, should be starting ahead of Cech.

There are some concerns over his shot-stopping ability, though it cannot be much worse than Petr at present. Now 36-years-old and unlikely to develop into Manuel Neuer-type confidence with the ball at his feet overnight, it's imperative Unai places his faith in Leno and quickly to make his possession-style work.