ST. PETERSBURG, Fla. -- A man caught on camera sucker punching another person has been sentenced to 18 months in jail. 

Zachary Allen pled guilty to felony battery after the incident in March of 2017. 

Allen is accused of sucker punching 26-year-old USF student Brian Neal, leaving him with serious injuries. 

The incident happened last St. Patrick's Day while a group of men were waiting in line at a hot dog stand in downtown St. Pete. 

Police said the group of guys had been cat calling some women who had walked by. Neal was standing nearby and his friend said that Neal didn't like the way the women were being treated, so he spoke up. 

The surveillance video shows Neal and the men arguing for a few minutes, then Allen, who detectives say is a trained Brazilian Jiu Jitsu fighter, can be seen quickly turning around and punching Neal in the face. The punch knocked Neal to the ground, causing him to hit his head on the sidewalk. Neal was sent to the hospital with a brain bleed, officials said. 

Witnesses say the punch was triggered by a derogatory mark Neal made about Allen's girlfriend. 

Allen turned himself in to police five days later and pled guilty.