The £86m world record signing from Tottenham is currently suffering from a 'disc protrusion' injury which Real Madrid’s chief doctor Carlos Diez claimed was 'not unusual.'
However another doctor, Dr Avelino Parajon, told Marca that the club should not have gone ahead with the transfer if they knew about the aliment.
"That is not to say that tomorrow it can be operated on and he can continue playing, like has happened many times.
"But if he already has problems with protruding discs, that indicates that it is not a one-off.
"When a person has those problems at that age, it suggests that he has a great possibility of suffering herniated discs and symptoms arising from that over time. It is a bad sign for any athlete."
Real's doctor Diez insisted there was nothing to be alarmed about and they were happy with Bale's medical at the club.
"When Bale had his medical no clinical condition was discovered, just a radiological finding.
"There’s no threat that he will need surgery, although, of course, to avoid any problem, he is undergoing a preventative recovery programme because we are obliged to make sure the player is protected and make sure this discovery doesn’t become anything bigger.
"Our view was that the player was ready and therefore there was nothing to report to the president."
Bale's agent Jonathan Barnett was also furious that Marca were making such a big issue about the injury.
"I spoke to a reporter from Marca, I told him: 'It’s complete rubbish', and yet they still print it. Whatever they say is a lie. How stupid and irresponsible of Marca to have run such a stupid story!," he told La Sexta.
"He passed the medical, he’s 100 per cent fit, there’s no problem.
"He's the most expensive transfer in history, if there was a problem, they would have stopped the transfer.
"There is no problem, he has a slight tear in his thigh, he’ll be fit to play hopefully after the internationals.
"He's back training normally and he’ll be playing in the next few days. It's up to Ancelotti when he plays, but he will play, he'll be fit to play."