Michael Schumacher was flown to the wrong hospital after his ski crash in the French Alps in December, according to reports.
Former F1 doctor Gary Hartstein says vital hours were lost as doctors took him to a local clinic instead of brain specialists when hit his head in the resort of Meribel.
According to The Sun, he said: "You do not take patients with a suspected head injury to hospitals that do not have neuro-surgical capability."
Schumacher was airlifted to Moutiers after hitting hitting his head on rocks, and was transferred to Grenoble University Hospital shortly afterwards.
According to the Daily Mail, Hartstein added that "usually impeccable sources" said that these lapses "could, and almost certainly did, worsen the outcome in Michael's case".
On Tuesday, Mr Hartstein said he believes Schumacher fans should prepare for "really bad news".
According to the Mirror, he wrote on his blog: "As time goes on it becomes less and less likely that Michael will emerge to any significant extent.
"I spent years at circuits drenched in red by the Ferrari caps, flags, and shirts, and all of that for Michael. I'm still staggered by the depth and persistence of his fans' love for him.
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