Sunderland manager Dick Advocaat has lamented his side's terrible start in the 2-0 defeat to Bournemouth on Saturday.
The Black Cats conceded twice in the opening nine minutes at the Vitality Stadium to succumb to a fourth defeat of the season and remain winless at the bottom of the Premier League table after their opening six matches.
Advocaat admitted that he is deeply concerned by Sunderland's 'losing mentality' after the defeat to the newly-promoted side.
"It is a big problem because mentality is difficult to change," he told reporters.
"Last week, we thought in training that it was getting better and better. But if you see what we did in the first half, it was unbelievable. I am very, very angry with the players because this is not the first time.
"After the game I said I will start thinking about myself. What did I do wrong? What are we doing during the week?"
Sunderland next face a trip to the Etihad to play Manchester City in the League Cup third round on Tuesday.
No Data Analysis info
