The fight between three men happened in Ive Farm Close just after 9.30pm yesterday (January 11), our sister site London Now reports.
Officers and London Ambulance Service crews attended and a man was found with head injuries, before being treated at the scene and taken to hospital.
The man was later arrested on suspicion of possession with intent to supply Class A drugs.
He has since been discharged from the hospital and remains in custody.
No other arrests have been made and enquiries are ongoing.
Anyone with information about the incident which may help officers is asked to call 101 quoting CAD 6031/11JAN.
To remain anonymous, contact the independent charity Crimestoppers on 0800 555 111.
