Sir Alex Ferguson has told Manchester United fans they are in danger of damaging his team's away form in the Barclays Premier League.
Last season 12 clubs refused to give United their full allocation of away tickets because of what they believe to be obstructive behaviour such as persistent standing and blocking walkways.
Now United boss Ferguson has got involved after their 3,000 allocation for the game at Liverpool on October 15 was reduced to 1,960.
Ferguson has written to all the United fans who do have a ticket, saying: 'Your support is a vital part of our success. The players notice when your numbers are cut.'