"It is a strange thing, football. It comes around and you have got to be careful."
West Ham manager David Moyes sounded that warning to Lyon before their Europa League quarter-final second leg, and he was right to.
Come full-time, the Hammers were celebrating a 3-0 victory that secured the club's first European semi-final for 46 years and helped banish some of the needle that had built up following the first leg.
Moussa Dembele's wink after drawing the foul which saw Aaron Cresswell sent off in the first encounter had certainly not gone unnoticed by the West Ham manager or his players.