Manchester United Will Sign Arturo Vidal if He Answers Van Gaal's Knee Questions, Says Chile Coach Sampaoli

Chile's national team manager Jorge Sampaoli has confirmed Manchester United want to sign Arturo Vidal, but are awaiting assurances over the condition of the midfielder's knee before pushing through the move.

Vidal was named in the Juventus squad for their preseason tour of Indonesia, Singapore and Australia on Sunday, in the club's biggest indication yet that he will not be leaving.

Yet despite this development and assurances from Juve manager Massimiliano Allegri, the Chile international remains linked with a move to Old Trafford amid suggestions Juventus will allow the player to leave for the right price.

And Sampaoli, who guided Chile to the knock-out stages of the World Cup in Brazil, has revealed United are ready to complete a £47.5m deal, providing manager Louis van Gaal can be convinced of the midfielder's long-term fitness after he underwent surgery on his right knee to resolve a meniscus injury three months ago.

Speaking to Chilean newspaper El Mecurio, Sampaoli said: "I know that right now the big obstacle facing his transfer from Juventus to United, for 80 million dollars (£47.5m), is the doubt of van Gaal regarding the improvement of Arturo's knee."

Sampaoli added that such was the extent of Vidal's injury and his hurried return to international duty that World Cup observers only saw the 27-year-old performing at "30 or 40 percent" of the level he usually performs at for the Bianconeri.

Vidal has been at the centre of speculation all summer regarding a possible move to United, whose manager van Gaal has been reluctant to discuss the possibility of new signings.

Ander Herrera and Luke Shaw have arrived this summer in the space of two days last month, but van Gaal has suggested he will prioritise strengthening United's defence during the remainder of the transfer window.