Arsene Wenger admits that Calum Chambers' red card at Stoke City killed Arsenal's hopes of completing a comeback.
The Gunners trailed 3-0 at half-time at the Britannia Stadium but hit back through Santi Cazorla and Aaron Ramsey before Chambers received a second yellow card with 11 minutes remaining.
"You come out of the game and you think it’s unbelievable that you come home with nothing out of the game because we didn’t start well"
"If you’re 3-2 up then you can’t get a better decision than one of the other team’s players getting sent off," said Wenger. "It was a killer.
"Calum is an easy target because he’s not a dirty player at all. The second yellow card - compared to what happened on the pitch - was a bit farcical.
"He’s only 19 years old and he has to learn [about positioning]. We were a bit young on Saturday at the back and defending is a job for older people. Koscielny couldn’t play and then you have to play defenders who are used to the defending positions."
Alongside Chambers was Per Mertesacker, who played in a slightly unfamiliar role on the left of the centre-back pairing.
"I still think he had a decent game," said Wenger. "It’s difficult to talk about individuals but as a unit at the back, we were not dominant enough in the first half.
"In the second half I didn’t see Stoke. You come out of the game and you think it’s unbelievable that you come home with nothing out of the game because we didn’t start well."
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