David Luiz made a calamitous howler to hand Manchester City a 1-0 lead against Arsenal at the Etihad Stadium on Wednesday evening.
The Brazilian centre-back was named on the bench but was brought on when Pablo Mari suffered an injury.
And it became clear why Mikel Arteta initially left him out in first half injury time when he hashed at a cross and failed to make solid contact with the ball.
Raheem Sterling capitalised on Luiz's error and lashed home to give the hosts a 1-0 lead.
It was an awful moment for the former Chelsea defender - and worse was to come.
The one-man horror show started with Luiz letting Sterling score and concluded with him being sent off.
Kevin De Bruyne scored from the result spot-kick and Man City had Luiz to thank for their 2-0 lead.
Luiz has now conceded four penalties in the Premier League this season and we can't imagine his teammates were very comforting towards him in the dressing-room at full-time.
Even before Luiz's errors, the evening was proving a difficult one for Mikel Arteta on his return to the Etihad Stadium.
He was forced into making two substitutes inside the first 30 minutes following injuries to Granit Xhaka and Mari.
You have to feel for Arteta. This was already going to be a difficult match and he wasn't helped by injuries and Luiz.
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