Tiemoue Bakayoko’s early red card reduced Chelsea to 10 men after just half an hour and they never recovered from that setback. Troy Deeney put Watford ahead from the spot before half-time, and despite Eden Hazard pulling one back, Watford could not be stopped.
Daryl Janmaat, Gerard Deulofeu and Roberto Pereyra all found the net in the final 10 minutes to see Conte suffer a second big defeat in a row.
The loss means Chelsea now sit just one point above fifth-placed Tottenham Hotspur in the battle for a Champions League spot, though they are just one point back of third-place Liverpool.
Conte has been vocal about his desire to remain , but the club has yet to deny the rumours suggesting he is on the hot seat, and this performance is unlikely to lessen the heat on the former Juventus and Italy boss.
Supporters on Twitter were quick to voice their displeasure at the Blues boss, who has underperformed this season despite leading the side to the Premier League last year.
