Observations made by Tony Beresford in Australia indicate that the object's position does not match any known piece of space junk.

BBC: New 'moon' found around Earth

The previous month linesman Cesar David Escribano was struck by an object thrown from the stands during a second division match at Cartagonova.

CNN: Soccer violence: Referees under siege

United's Rio Ferdinand spoke briefly to host Dermot O'Leary after suffering a cut eye as he appeared to be struck by an object thrown during the celebrations at the end of the match.

BBC: James Arthur wins X Factor final

After the match it emerged that a steward needed hospital treatment after being hit by a flying object following Adebayor's celebrations.

BBC: Adebayor handed three-match ban