Sokratis Papastathopoulos may have a few questions to answer after gifting Watford a goal on Sunday.
The powerful Greek defender simply handed the Hornets a way back into the clash on a silver platter as he tried to play the ball out from the back.
Bernd Leno slid the ball to Sokratis from a goal kick before the defender proceeded to gently stroke the ball straight to Watford player before Nathan Cleverly smashed it home.
You can watch the incident below:
Need a definition for 'calamitous defending'? Well there you go.
After cruising to a comfortable lead in the first half, it is sadly typical of the Gunners to put themselves under pressure unnecessarily.
In fact, the London side are the most error-prone bunch in the land having, made a staggering 14 errors leading to goals in the past two seasons.
Just to make things worse, the Gunners would later concede a penalty, giving Watford a golden opportunity to equalise.
It was an opportunity they gladly took.
If the Gunners really want to reclaim their place at the top table of European football, they are going to have to stop shooting themselves in the foot.
Somewhere in the bowels of Vicarage Road though, a certain Granit Xhaka is probably quietly smiling that for once it wasn't his fault.
That is two points most certainly thrown away.