A terrible error by Sokratis gifted Watford their first goal

Emery's men were playing better than their opponents on the field of play and their star striker put them two goals ahead. But the advantage was reduced when the home side scored their first goal of the match. 

Cleverley scored it. He took advantage of a clear error by Sokratis when he tried to play the ball out from the back. Deulofeu was alert and deflected the pass straight to his teammate, who made no mistake when he had the chance to score. 

That changed the game completely. Arsenal had it under control, but the goal lifted the home side and went looking for the equaliser. 

The defender's mistake was very bad because he was very close to his own goal. Cleverley only had to wait for the deflection from Deulofeu to fire home. Sokratis was clearly affected by his grave error.