A murder-accused PC Tasered an ex-footballer for six times longer than is standard before kicking him twice in the head, a court heard.
PC Benjamin Monk is charged with the murder of Dalian Atkinson during an altercation in Shropshire, in 2016.
He appeared at Birmingham Crown Court for the first day of his trial with co-accused PC Mary Ellen Bettley-Smith, who is charged with assault.
The former Aston Villa star died after he was Tasered for 33 seconds.
Prosecutors said the default setting for a Taser is five seconds but Mr Monk continued to press the trigger, overriding the system for 33 seconds.
Mr Monk and Ms Bettley-Smith, officers with West Mercia Police, arrived at Mr Atkinson’s father’s house on Meadow Close shortly before 01:30 on 15 August after neighbours had reported Mr Atkinson acting strangely and shouting in the street.
The court heard Mr Monk Tasered Mr Atkinson, who had serious health problems, three times after he came to the door acting erratically and claiming to be the Messiah.
The first two attempts were ineffective but on the third Mr Atkinson fell to the ground.
While he was unresponsive, the court heard the police officers “set about him”.
Mr Monk kicked him in the head with such force imprints of his boot laces were left in two locations on Mr Atkinson’s forehead while Ms Bettley-Smith used her baton to strike him “a number of times” while he lay still in the road.
Both officers deny wrongdoing however it is the prosecution’s case that their use of force was excessive and sustained while Mr Atkinson posed no threat.
Mr Atkinson, who had a long sporting career at a number of clubs, died in hospital at about 02:45 that morning.
He had been suffering with high blood pressure, heart disease and end-stage renal failure.
The trial continues.