The emergency services were called to Yiewsley Recreation Ground in West Drayton shortly after 2pm today (April 23).
Officers and paramedics found a man in his 30s with injuries to his leg and belly and he was taken to hospital.
His injuries are thought not to be life-threatening or changing.
A second man, 34, had face injuries and was also taken to hospital, but his condition is not yet known.
A 34-year-old man was arrested on suspicion of affray and grievous bodily harm.
It is believed that the two injured men knew each other and police have said there is no wider risk to the public.
Local officers will be present in the area and carrying out additional patrols.
A London Ambulance Service spokesperson said: “We were called at 2.03pm today (23 April) to reports of an assault in Albert Road, Yiewsley.
“We sent an ambulance crew, two paramedics in fast response cars and an incident response officer to the scene.
“We treated a patient at the scene and took him to hospital.”
Falling Lane was closed by police following the incident, and is yet to reopen.
Anyone with information is asked to call the police on 101 and quote CAD reference 3859/23APR25.
