A man will face court charged with manslaughter after a man died from injuries sustained during an alleged brawl.

The 37-year-old is alleged to have gotten into the fight with a 40-year-old man at a worksite on Bunbar Rd in Gymea Bay, south Sydney, about 3.20pm on March 3.

Paramedics arrived at the worksite and found the man had suffered “serious head injuries and was taken to hospital”.

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Police were called to St George Hospital on Monday after it was allegedly determined his injuries were not consistent with a fall.

It will be alleged the younger man assaulted the older during an argument before he fell backwards and struck his head on the roadway.

He died from the injuries on Monday.

The 37-year-old was arrested by police in Kogarah about 1.50pm on Thursday and charged with manslaughter.

He was refused bail and is expected to appear before Sutherland Local Court on Friday.