Newcastle United forward Nile Ranger was arrested on Saturday after a man was assaulted outside a pub and left unconscious with a suspected broken jaw.
The 20-year-old was arrested in Newcastle city centre at 1:30am (0030 GMT) and the victim was taken to hospital.
"Police were called after a 33-year-old man was assaulted," a Northumbria Police spokeswoman said.
"When police arrived, the injured man was unconscious and was taken to the Royal Victoria Infirmary suffering from a suspected broken jaw."
"The offender made off and police carried out a search of the area."
"A 20-year-old man was arrested a short time later, nearby, on suspicion of assault and is currently helping police with their inquiries."
Ranger joined Newcastle from Southampton in 2008 and played several games as the Magpies won the second-tier Championship and promotion to the English Premier League in 2010.
The north Londoner has made several appearances for the England under-19 team.
He was spoken to by his club in May after a photograph of him posing with a replica handgun appeared in a national newspaper.
Ranger has yet to feature for Newcastle this season.
The Magpies are at home to Fulham on Sunday.