Police in Buenos Aires have searched the house and private clinic of Leopoldo Luque as they try to establish if there was negligence in Maradona’s treatment following surgery.
The 60-year-old died of a heart attack at his home where he was recuperating.
His daughters have pressed for details about their father’s medication.
Maradona had a successful operation on a brain blood clot earlier in November and was due to be treated for alcohol dependency.
Dr Luque has stressed that he is co-operating with the authorities and that he had done his best for Maradona until the very end.
Some 30 police officers began the early morning raid on Dr Luque’s house – with another 30 going into his clinic in Buenos Aires.
The raids were ordered by prosecutors trying to build a picture of Maradona’s last days at home.
There are suspicions that the star’s convalescence at home might not have met the conditions of his discharge from the clinic, such as a 24-hour team of nurses “specialised in substance abuse”, the on-call presence of doctors and a stand-by ambulance equipped with a defibrillator.
Officials want to know how often Dr Luque, who was the footballer’s personal doctor, went to see Maradona at his house.