A 32-year-old man paid a steep price for chivalry early Saturday morning: a suspect beat him repeatedly in the head with a metal rod.

Around 2 a.m., the suspect approached the man and his girlfriend near the intersection of 16th and Valencia streets and began making “inappropriate sexual remarks” to the woman, San Francisco police spokesman Albie Esparza said.

The boyfriend told the suspect – a man who looked to be in his mid-to-late 20s – to leave her alone. He did, and then turned on the boyfriend, striking him in the head multiple times with the blunt instrument, police said.

As the suspect was fleeing the scene, he also used the rod against a 30-year-old woman who witnessed the incident, police said.

The boyfriend, bleeding from cuts on the back of his head and forehead, was admitted to San Francisco General Hospital. The second victim complained to police of neck and back pain, but declined medical treatment. The girlfriend was not harmed.

Esparza described the suspect as about 5′ 10″ and 180 lbs., with a shaved head and dressed in a white shirt and dark pants. Police later recovered the weapon on Mission Street, but no arrests have been made. Esparza said it was an unfortunate case, considering the victim “was just trying to defend his girlfriend.”

“Thankfully the victim was not too seriously injured,” Esparza said.