FALMOUTH, Mass. — A man was ordered held without bail yesterday for allegedly beating a New York man with a baseball bat because he thought the man was a Yankees fan.

As it turned out, the New Yorker allegedly beaten in the land of the Red Sox isn’t even a big baseball fan.

Police say Robert Correia, 20, and others spotted a car with New York license plates leaving a fireworks display Friday. The group approached the car and began yelling about the Yankees, according to the police report.

Police did not identify the victim, but the New York Post identified him as William Nestor, 29, of Northport, N.Y. Mr. Nestor said his family was traveling in two cars and stuck in heavy traffic after the fireworks on Cape Cod when he was attacked.

“When they saw the plates, they came at me,” Mr. Nestor told the newspaper.

The police report said after Mr. Nestor confronted the group of men, Mr. Correia went to his nearby apartment in Falmouth and got an aluminum baseball bat, then struck Mr. Nestor three times.

But Mr. Correia’s lawyer, Robert Nolan, said the man was in his apartment when he noticed a fight outside and grabbed a bat to try to break it up.

Mr. Correia told Mr. Nestor to drive away, but Mr. Nestor “came at him” as if he was going to hit him, Mr. Nolan said. Mr. Correia said he struck Nestor once with the bat.

“He said in self-defense, he swung the bat at the guy and hit him in the arm,” the lawyer said.

Mr. Nolan said Mr. Correia did not participate in any Yankees taunting.

“He was trying to defuse the situation,” Mr. Nolan said. “The mistake was probably to bring the bat out there.”

Mr. Correia pleaded not guilty to charges of assault and battery with a dangerous weapon and malicious damage to a motor vehicle. He was ordered held without bail until a hearing tomorrow.

Mr. Nestor said he’s not a particularly big baseball fan and didn’t know the Red Sox were playing the rival Yankees over the weekend. He was treated and released from Falmouth Hospital.