Arturo Vidal
Vidal was at the centre of a transfer saga in the summer. Getty

Manchester United manager Louis van Gaal's decision not to sign Juventus and Chile midfielder Arturo Vidal over fears regarding recent knee surgery appear to have been justified after the 27 year old reportedly broke down in training while on international duty.

Vidal underwent a procedure on a meniscus injury before the World Cup and though he played a full part as Chile reached the second round, United were understood to have been put off by the Juve player's fragile fitness.

Despite being urged by supporters to make Vidal among a host of new arrivals at Old Trafford, United's cautious approach appears to have paid dividends after reports in Chile claimed Vidal broke down during a routine training session in Miami ahead of matches against Mexico and Haiti.

The player is now expected to withdraw from the squad and return to Italy for further assessment, while Serie A champions Juventus will be hoping Vidal has not suffered a recurrence of the injury which saw him miss the back end of last season.

Chile national team manager Jorge Sampaoli claimed that United were interested in signing Vidal in the window but that Van Gaal has grave concerns over the player's injury history.

"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," he said.

United were heavily linked with a move for Vidal up until the final hours of the summer transfer window as the club embarked on a record-breaking spending spree in order to kick-start their hopes of qualifying for next season's Champions League.

Juventus were continually evasive over Vidal's future during the off-season but manager Massimiliano Allegri has confirmed since the closure of the window that their prized asset was never for sale.

"Vidal? He was never on the market," Allegri told Sky Italia. "The club told me from the start that he would stay.

"I'm happy with the business the club did," added Allegri. "The aim was to carry out targeted operations, not to buy just for the sake of buying. Ours was an intelligent transfer market.

"We would have only done something more if we had found a player that would have really lifted the level of the squad."