The 27-year-old was the Gunners best player according the WhoScored and received a rating of 8.3.
Ozil made the most key passes during the game (6) and took the most touches on the ball (117).
The Germany international also made 6 successful dribbles, two tackles and maintained a passing accuracy of 88%.
The defeat was Ozil’s first in the FA Cup since joining Arsenal on a record £42.5 million move from Real Madrid in 2013.
Watford took the lead on 50 minutes when Ighalo made the most of poor defending from Arsenal to find the back of the net.
The visiyors went onto to double their lead when Guedioura blazed the ball into the top corner almost ripping the net in the process.
Arsenal did rally late on and Mesut Ozil set Danny Welbeck up with a cheeky back-heel to half Watford’s lead.