David Moyes criticised the supporter who ran onto the pitch and ruined a promising West Ham attack during the 1-1 Europa League draw with Lyon.
A historic match for the Hammers ended on a sour note after a pitch invader - the second of the game - jumped out of the home end with 10-man West Ham actually mounting a rare attack.
'I was baffled,' said the West Ham boss. 'This is a really good football club doing so many good things.
'But those things tonight didn't help, we were on a counter-attack with an opportunity to score.