Authorities in Braintree say the man was arrested Thursday afternoon during a traffic stop.
The suspect has been identified as 20-year-old Brandon Jones, of Braintree. Braintree police say he's charged with assault and battery.
It happened in the balcony of the arena. Boston police officer James Kenneally said the suspect used a box cutter in the attack, according to The Boston Globe. The victim was taken to a Boston hospital with non-life-threatening injuries.
Braintree police Lt. Michael Moschella says officers found the suspect after Boston police sent out a description of him.
It's unclear if Jones has a lawyer. His arraignment is scheduled for Friday.
The Associated Press contributed to this report.