The injured biker was taken to Government Rajiv Gandhi General Hospital, where he is still being treated.
The doctor did not bother to check the biker's condition after ramming the motorcycle in a high speed near a roundabout at Anna Nagar in central Chennai, police said in a statement.
After the accident, the Audi driver sped away "with the intention of escaping" and hit a traffic signal pole while taking a U-turn, police said.
Police have taken his driving licence and will ask the transport authorities to cancel it. Further investigation is on.
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