The suspects apparently jumped the victim after getting onto a verbal dispute in front of Riviera Cafe.
Eyewitness News is told the victim sustained life-threatening injuries to the back of his head. He was rushed to St. Vincent's Hospital in critical condition.
Witnesses reported seeing at least two men flee the scene.
No arrests were immediately made, and police have not determined a possible motive other than the verbal dispute.
No weapon was recovered, and detectives believe the suspects beat their victim with their bare hands.
A large pool of blood and the man's shirt were left in the street.
The attack was the latest in a noticeable uptick in assaults in the generally crime-free neighborhood.
On May 3, a 28-year-old Upper East Side man was attacked on Christopher Street near Washington Street at around 2 a.m.
The suspects reportedly broke his jaw and fled.
For more on the Anit-Violence project, go to http://www.avp.org or call the Hotline at: 212-714-1141.
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