Police said the stabbing was just before 10 p.m. in front of the Starbucks at the intersection of Route 66 and Lone Hill Avenue.
The victim was in the patio area of the Starbucks when he saw a woman being beaten up and tried to help. He ended up being stabbed several times by her attackers, a slash wound to the neck, another to the top of his head and several wounds to his chest.
The man was airlifted to County-USC Medical Center and is expected to survive.
Anyone with information is asked to call Glendora Police at (626) 914-8250.
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