Abdoulaye Doucoure punched in a 90th-minute equaliser to fire up the Premier League's video technology debate as Troy Deeney admitted Watford got away with one.
Doucoure converted Deeney's cross with his hand to level up against Southampton - but referee Roger East failed to spot the foul.
After the virtual assistant referee (VAR) was trialled in the FA and Carabao Cups this week, the Premier League was left lacking.
'I played the header so I didn't see it,' Deeney said last night.