Arsenal squandered a two-goal lead as Watford hit back to draw 2-2 in new manager Quique Sanchez Flores's first game of his second stint in charge at Vicarage Road on Sunday.
Flores's return following the dismissal of Javi Gracia after four games of the Premier League season seemed to be going flat as Pierre-Emerick Aubameyang struck twice in the first half.
But Tom Cleverley halved the deficit in the 53rd minute after some dreadful Arsenal carelessness and Watford were rewarded for a much-improved display when substitute Roberto Pereyra converted an 81st-minute penalty awarded after he was brought down by David Luiz.
Watford came agonisingly close to winning it with Gerard Deulofeu curling just wide and then Abdoulaye Doucoure having stoppage-time shot saved by Bernd Leno after a counter-attack.
Victory would have put Arsenal into third place but they ended the day seventh in a cluster of clubs on eight points.
Watford are still seeking a first win of the season and remain bottom but they doubled their points tally to two.
