Sunderland boss Gus Poyet has admitted that his players were angry after their 2-0 defeat to Arsenal in the Premier League on Saturday.
The Black Cats lost for the second game in a row as costly mistakes from Wes Brown and Vito Mannone allowed Alexis Sanchez to net a brace at the Stadium of Light.
Poyet has revealed that he was pleased to see a response from their 8-0 hammering at the hands of Southampton, but is adamant that his side cannot afford to keep making errors.
He told reporters: "The commitment, reaction, desire and organisation were there compared to last week.
"We forgot to leave the mistakes in the dressing room. I don't know if it is tension, or lack of whatever you want to call it, but unfortunately we lost to two mistakes.
"There is anger in the dressing room. We tried and fought hard for the result and then two actions have cost us."
Sunderland are 17th in the Premier League table following their defeat to the Gunners.
