"He went to the outside of the corner and went to the ditch. The ditch was ending and the car hit the end of the ditch with a strong impact on Hayden's side.
"They both came out of the car themselves, then Hayden started to have some lower back pain, so they decided to ask for a doctor.
"The ambulance came, it took them back to the start and Hayden was airlifted to the hospital in Porto where they are doing a check-up."
Paddon was able to exit the car himself but was suffering from lower back pain and taken to a Porto hospital, co-driver Seb Marshall was not injured in the crash.
The 31-year-old said he was glad to be leaving hospital, but was "very disappointed in the result for the team and myself", in a social media post.
"At this level the margins are so small and if we want to take it easy and drive around all the rocks/holes/bumps etc then we are outside the top 10.
"Modern day WRC is flat out and our apex of the corner was comprised by 10-15cm - that's the margins we are talking, but at the same time, why we love the WRC," Paddon said.
He, and co-driver Marshall will be ready to go for the Rally Italia Sardegna between June 7-10 with some rest and recuperation.
"It's good to know that we had strong pace, the feeling with the car is good and we are still positive for the future," Paddon said.
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