Fernando Alonso is sitting out the Bahrain grand prix with broken ribs and after suffering a partially collapsed lung.
The Spaniard made the revelation on Thursday, after FIA doctors studied CT scans and ordered him out of the McLaren-Honda this weekend.
Alonso told reporters he suffered a "pneumothorax", or partially collapsed lung, due to the G-forces of his high-speed crash in Melbourne.
But he said that is no longer a problem and he is not suffering any "respiratory problems", but ribs on the left side of his chest are broken.
He will now bid to recover in time for China.
"It’s not 100 per cent," Alonso said of his chances. "It will be another test I need to do in the next 8 to 10 days.
"I was ready to go through the pain somehow and make sure I could race, or at least try, but the first thing is safety and so I understand (the decision)."
German driver Nico Hulkenberg said he is not too surprised Alonso is having to sit out the weekend.
"Yes and no," said the Force India driver. "Immediately after the accident he seemed to be ok, but I saw on Monday that he complained of rib pain. And ribs are always a tricky thing."
Alonso said on Thursday that he would have liked a "halo" device to protect his head during his crash, but Hulkenberg disagrees.
"I would like to see how fast he could have got out of the car with halo," said the German. "I am still against it."