Merseyside Police says it is looking into CCTV footage that appears to show Everton midfielder Ross Barkley being punched during a night out.
It is claimed the security video shows the 23-year-old England player being hit in the face by a man in a Liverpool bar in the early hours of Monday.
Everton have not commented and no complaint has been made to police, but they are viewing the footage.
Barkley played 90 minutes in the Toffees' win over Leicester on Sunday.