Fernando Alonso has revealed his Australian Grand Prix Formula 1 crash left him with broken ribs, a pneumothorax and the risk of further lung damage.
The McLaren driver will sit out this weekend's Bahrain GP, with GP2 champion and team reserve Stoffel Vandoorne making his F1 racing debut in Alonso's place.
Alonso had a violent accident when he ran into the back of Esteban Gutierrez's Haas in Melbourne.
Though given the all-clear by the medical team at the time, he explained that pain in his chest increased in the following days - prompting a CT scan and the discovery of a small lung collapse and "some rib fractures".
He explained that the problem was not the pain level but the danger of additional consequences.
"The risk is driving because in F1 there is a unique position in the car and with the g-forces the fracture could move into the lung as well," said Alonso.
"This is not a broken leg or a broken arm where you can deal with pain.
"This is in the chest where there are some organs.
"The problem is the rib [damage] is too fresh, and still not completely improved.
"The risks are small but we all want zero risk."
Alonso was officially sidelined from the Bahrain race when he had an FIA medical examination at Sakhir on Thursday morning.
He expects to undergo another set of checks "in the next eight or 10 days" to determine whether he can race in the next event in China in a fortnight.
"I'm disappointed - obviously we want to race," Alonso said.
"When you come here and you cannot even try, it's sad.
"It's understandable. I respect the decision.
"I tried until the last moment to be able to race.
"There have been some painful days with some pain at home but I was ready to go through this pain somehow in the car and make sure I could race.
"At the end of the day, the pain is manageable if you don't think too much.
"The doctors think it's a risk, I understand."
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