Naby Keita, who has been linked with both Arsenal and Liverpool, collapsed after RB Leipzig’s defeat to Wolfsburg because of a ‘circulatory collapse’.

The 22-year-old midfielder passed out in the dressing room on Saturday after his side had lost 1-0 to Wolfsburg, a game in which he had played the full 90 minutes.

Exertion has been put forward as one possible explanation for the problem but doctors seem at a loss as to the exact cause.

Speaking on Sunday, manager Ralph Hasenhuttl, said, “He spent the night in hospital and he’s feeling better. All the test results are okay.

“It seemed to be the fault of his circulation, he burnt himself out yesterday.

“For sure, we will continue to look for causes in the next few days.

“It was probably a combination of several factors. I am glad that there is no deeper disorder. His test results were all okay, that is why we have to look at what was the cause.”