Manchester United striker Federico Macheda was robbed in his home by two thieves who stole money and jewellery, police said on Monday.
The 17-year-old Italian was targeted at his house in Washway Road, Sale, at 3.40am on Sunday; while his friend was attacked and suffered minor head injuries during the robbery.
A spokesman for Greater Manchester Police said: "Two men stole cash and jewellery from the victims before running out of the house.
"One man suffered a minor cut to his head in the robbery. Inquiries are ongoing."
The police spokesman was unable to confirm reports that the attack was linked to a row earlier in the evening outside a Manchester city centre nightclub.