The victim, who said his name was Steve but did not reveal his last name, said he was on the train at about 11:15 p.m. when he noticed a white male swearing and behaving erratically inside the same train car he was on.
Steve said he was in town on business and is not a Portland resident. He left for home Friday morning. He did not say where he lived.
Steve told KATU News in an exclusive interview that the suspect in the random, unprovoked attack accused him of being a "racist bastard" while both of them were on the train. Both Steve and his attacker are white.
Steve said that when he got off the train, the suspect came at him with a large, metal U-shaped bike lock, struck him several times in the head and then ran off. He said the suspect, while not a large person, was "pretty strong."
He described the suspect as a young white male with long blond hair and about 5 foot 6 inches to 5 foot 8 inches tall. Steve also said that while on the train before the attack, he overheard that the man was a dishwasher.
The incident took place at the North Prescott Street station, the same location as another recent incident that left a woman injured after she was set upon by a group of teens after she stepped in to protect another rider.
Paramedics attended to Steve at the scene and he was released without requiring hospitalization. However, he said he had some deep bruising and cuts on his head, chest and shoulder from the attack.
Steve said he was "keeping an eye on" his attacker while he was on the train but did not do anything to provoke the attack. He said the suspect was acting "really weird."
Police and transit officials plan to review video surveillance from the station as part of an investigation.
TriMet officials said there were six security officers along the Yellow Line at the time but that none were at the Prescott Street Station at the time of the attack.
The Yellow Line runs along Interstate Avenue in north Portland and terminates at the Expo Center near the Columbia River.
"I would just hope that the people of Portland would not stand for this kind of thing anymore and would want to take some action to protect the citizens and visitors to this city," Steve said.
Two teens will be tried as adults in the attack on a woman at the Prescott Street Station last week. Police initially apprehended a total of five people related to the attack. The woman who was attacked was taking her first ride on the MAX light rail system.
Recent problems with crime have led TriMet to increase security and revise policies in a bid to cut down on violent incidents on board MAX trains and near MAX stations.
In the attack involving the woman and the group of teens, the victim said she did not get any verbal confirmation from the driver that help was coming. A TriMet official said the driver acted properly, but a new policy requiring "verbal cues" from the train's driver will be required in an emergency situation.
An investigation is continuing into the incident that took place Thursday night.
TriMet and Portland police are asking that anyone who has information about the suspect or witnessed the attack to contact them immediately.
The victim of Thursday's attack sits in an ambulance while a police officer asks questions.