William Saliba has been warned that he would be expected to perform as soon as he becomes an Arsenal player in the summer but has been backed to come good for the Gunners.
Saliba joined Arsenal for £27million in the summer but the Gunners loaned him back to Saint Etienne to continue his development.
Injuries have curtailed his progress this season, but he has still managed to make 17 appearances for his side and has led them to the French Cup final.
He is set to become an important member of the Arsenal first-team when he eventually joins up with his parent club in the summer, but Bakary Sagna has warned him that he would have to hit the ground running immediately.
The former Arsenal star who spent seven years with the Gunners under Arsene Wenger has urged Saliba to copy the way Kylian Mbappe goes about his business confidently.
“First he will need to adapt to English football,” the 37-year-old, told Goal.
“He is a big prospect for the future but Arsenal need him to perform as soon as he starts.
“He is aware of that probably, but he has a lot of qualities and he will learn fast.
“Hopefully he will achieve good things and become one of the best centre-backs in the league.
“He is very confident in defending, he is not afraid to defend one against one and most of the time he wins the duels, which is the best quality as a defender.
“You need some security, you need some presence and he has that.
“For him, staying in the French league after signing for Arsenal was the best decision he could make because he knew he was going to change to a bigger club, but he knew he had to improve his performances.
“It was like a test, he had to step up his game during this season and the last game I watched of him was amazing.
“I analysed him as an Arsenal fan and he did very well.
“Someone who has always said don’t speak about my age is Kylian Mbappe.
“When he started saying this he was 19 and now he’s one of the best strikers in the world.
“If he [Saliba] believes he can be as good as [Virgil] van Dijk, he’s probably been watching his games and analysing them. It’s about hard work.
“If you want to be the best at the back, it’s all about work and belief.”