It happened around 3:00 p.m. Monday on the platform at Broad and Fairmount in North Philadelphia.
Surveillance cameras captured it all as SEPTA police officer Ron Jones confronted the man. Police say the suspect claimed he had a gun.
The suspect charged at the officer, who barely had any time to think.
Ofc. Jones pulled out pepper spray. But it was no match for the suspect, who investigators believe was strung out on drugs and suffers from mental illness.
Ofc. Jones whipped out his baton but the suspect kept coming, throwing the officer on the ground and up against the platform wall.
The no-holds-barred struggle continued as dozens of SEPTA riders ran off the southbound Broad Street train. Many were in shock.
Police say the man even tried to get the officer's gun. It wasn't long before a few Good Samaritans rushed over to help subdue the suspect.
Only Action News was there after Ofc. Jones gave a statement to Central Detectives about his life-or-death struggle.
"Thank the public for assisting me in what was going on today at Fairmount. Thank you," said Jones.
What was that moment like for him?
"Everyday life. I live it," he said.
However, the violent encounter didn't end even after the suspect was subdued.
The suspect overpowered the men on top of him and ran back onto the train, where police say he tried to grab a child from his mother.
Riders scattered, sparking an even more chaotic scene underground.
Backup finally arrived and the man was taken into custody. Police say he did not actually have a weapon.
"The officer being by himself, that's a tough situation to manage. He did his job. He did a tactical approach to the situation and he used great restraint," said Inspector Steven Harold, SEPTA Transit Police.
Top SEPTA officials and witnesses hailed Ofc. Jones as a hero. The 5-year veteran, who suffered only a jammed finger after the subway platform attack, humbly disagreed.
"No hero, no hero," he said.
Ofc. Jones said he would be back on the job Tuesday.
As for the suspect, whose identity has not been released - he was taken to Hahnemann Hospital for treatment. He will also undergo a mental evaluation.