A man was arrested for allegedly stabbing another man in the bathroom of Red Ivy, at 3525 North Clark St., during the Twelve Bars of Christmas bar crawl. View Full Caption DNAinfo/Serena Dai

WRIGLEYVILLE — The victim of a beer bottle stabbing during a Wrigleyville holiday bar crawl was bleeding so much he looked "like Friday the 13th," said a bar security manager, referring to the slasher films.

The gruesome scene unfolded after midnight during Saturday's Twelve Bars of Christmas, or TBOX, a pub crawl that starts at about 8 a.m. and continues late into the night. A man allegedly jumped out of a bathroom stall at sports bar Red Ivy, 3525 N. Clark St., and stabbed another man in the neck with a broken beer bottle, police said. A man who saw the attack came to victim's aid and helped keep the offender at bay until officers arrived, police said.

Both the victim and the alleged assailant, a 23-year-old man from Uptown, wore holiday gear such as ugly Christmas sweaters and Santa hats at the time, said Robert Davis, security manager of Red Ivy, a large Cleveland Browns bar located near the intersection of Clark and West Addison Street.

Gregg Greaves, 23, of the 4700 block of North Beacon Street, was charged with a felony count of aggravated battery causing great bodily harm after he allegedly stabbed a man in the neck with a broken beer bottle during Wrigleyville's Twelve Bars of Christmas, or TBOX. View Full Caption Chicago Police Department

The victim, also in his 20s, walked out of the bathrom bleeding, holding his hands over his neck, Davis said. The man applied dry napkins to the wound until paramedics arrived, Davis said. He also suffered cuts on his chin and hands from pushing his alleged attacker away, police said.

"You see a lot of bad [things], but as far as initiating a wound, that was the worst [I've seen]," Davis said. "It was rough."

Bar security carried the alleged assailant out of the bathroom and lay him on the ground in an attempt to keep him still because he had the victim's blood all over him, Davis said. The man had been in the bar for about half an hour before the altercation. He seemed oblivious to what had happened and appeared to be "under the influence of more than alcohol," Davis said.

"You work at a bar, you know [when it's drugs]," he said.

Officers arrested Gregg Greaves, of the 4700 block of North Beacon Street, and charged him with a felony count of aggravated battery causing great bodily harm. He's scheduled to appear in bond court on Monday.

The victim was treated at Advocate Illinois Masonic Medical Center, police said.

"Everybody was completely annihilated," Davis said as he shook his head. "You hate to see that happen, but it's the bar business."

Police could not confirm media reports that said the man defecated into his hands and threw feces onto the floor once he was in custody.