Man bashed twice in Sydney attack

A young man has been bashed unconscious by a gang in a suspected gay-hate crime in inner Sydney.

As Mardi Gras approaches, detectives are investigating whether the victim's sexual orientation was the reason for the attack as he walked home in Waterloo on Sunday morning.

The 22-year-old was punched and kicked until he lost consciousness after being confronted by a group of men and women in McEvoy Street about 1am.

He woke a short time later on nearby Waterloo Oval where he was assaulted again, officers say.

As well as a possible head injury he suffered multiple facial fractures as well as tooth and palate damage.

In a separate attack, two men were injured by two other men in Surry Hills on Saturday morning.

"The occurrence of two bias-related assaults over one weekend is not common, and of concern to police," NSW Police Sexuality and Gender Diversity spokesman Superintendent Tony Crandell said on Tuesday.

"With Mardi Gras season upon us and with larger numbers of people visiting Sydney's inner suburbs, help police to keep you safe by being aware of our surroundings at all times and calling triple zero if you feel under threat."

Police have warned people to stick to major routes, use well lit paths, stay in groups and change direction if they fear they're being followed.