Jenson Button believes Ferrari’s Sebastian Vettel is in for a challenging year with the arrival of Charles Leclerc as team-mate.

The highly rated youngster joins the Prancing Horse from Sauber, where he starred during his debut season and was promoted from the Ferrari Driver Academy role into a race seat in favour of Kimi Raikkonen.

Coupled with the pressures of not having won a world championship with Ferrari, Button suggests 2019 will therefore be an important year for Vettel.

“I think it’s a very different atmosphere for Sebastian at Ferrari than it was a Red Bull, maybe there’s more pressure,” Button told Sky Sports.

“We’re going to see how he copes this year. It’s going to be a big year for Sebastian.

“When Daniel Ricciardo came into Red Bull he found it difficult – he put him under a lot of pressure and actually out-performed him.

“I think if Charles can do that this year it’s a tough decision of where Sebastian’s going to for the future, and what he’s going to do. It’s an important year for him.

“I’m sure he feels the pressure and we’ll see how he copes under the pressure because he’s an unbelievably skilled driver, and super fast, but if your mind isn’t in the right place, forget it.

“Charles seems such a happy go lucky go, so relaxed, I think the team are going to really take to him and that sometimes can hurt the other driver.”

Button also believes Red Bull will have to step up its game and provide Max Verstappen with a car capable of challenging for the title as the Dutchman looks to continue his meteoric rise in the sport.

“Max will get the maximum out of a car and a little bit more. In tricky conditions Max is fantastic with a car,” he reasoned.

“But Max is a tricky one because he’s always moving forward, he’s always looking for something else.

“So this is an important year to keep it moving so he has to be really fighting for the championship or I think he’s going to start asking question of where he’s got to be in future.”

Verstappen will be joined by the freshly promoted Pierre Gasly in 2019 after Ricciardo opted to leave the squad for Renault.

Among the front three teams it leaves only Mercedes with an unchanged driver line-up with Hamilton again joined by Valtteri Bottas.