The Gunners were held to a 3-3 draw with Anderlecht in the Champions League on Tuesday night despite holding a three-goal lead with half-hour remaining at The Emirates.
Arsenal manager Arsene Wenger signed Mathieu Debuchy in the summer, but a string of injuries have forced the Frenchman to play Nacho Monreal out-of-position at centre-half.
And former Republic of Ireland international Giles reckons Wenger is incapable of organising his defence, leading to the north London side conceding plenty of goals.
“It has been the pattern for Arsenal. If you’re an Arsenal supporter, you’ll be very frustrated,” Giles told Off The Ball.
“But you look at Arsene Wenger. He has been a great manager for them over the years but since he inherited the good defence with Adams and co, he hasn’t had a good defence since.
“Wenger can’t organise a defence. He is another high line man. There is no way you should lose a 3-0 goal lead at home. You have to be able to tie the game up.
“They’re giving far too many goals away to win things.”
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