Manchester United captain Nemanja Vidic has blasted teammates after their 2-2 draw at Bolton Wanderers. United conceded twice against Bolton on Sunday as they were held to a shock draw.
It takes their tally to 11 goals against from their eight matches in all competitions this season.
United skipper Vidic said: "Yes, we're concerned. Over the last few years we haven't conceded many goals.
"We always looked strong and we didn't give teams many chances.
"But in the last few away games we haven't kept clean sheets, which is very disappointing."