A fisherman who was chased into the water and shot in the leg at Adelaide's West Beach in February 2019 has told a court his leg needs to be amputated and he will never "walk on his own two feet again". William Cowling, 37, pleaded guilty to aggravated assault causing serious harm with intent and several firearms offences.

The District Court of South Australia heard Cowling had consumed large quantities of alcohol before he challenged Theo Papadopoulos — a fellow fisherman — to a fight at West Beach in February 2019.

Mr Papadopoulos refused but Cowling later returned wearing a mask and gloves, chased Mr Papadopoulos into the water and shot him.

In a victim impact statement read to the court, Theo Papadopoulos said he had been living in a hospital gown since the incident as he required numerous surgeries and regular hospital visits.

The court heard his leg now needed to be amputated above the knee. Cowling has been in custody since February 2019. He will be sentenced next month.

He will be sentenced next month.