Manchester City goalkeeper Joe Hart has warned fans about their behaviour ahead of this Sunday's derby against Manchester United.
The fixture last season was marred by trouble from the supporters, one of whom had to be restrained by Hart after invading the pitch.
United defender Rio Ferdinand was also hit in the face with a coin thrown from the crowd during the 3-2 win for the Red Devils at the Etihad Stadium.
"There were incidents last year which no-one wants to see repeated," the Daily Mail quotes Hart as saying. "The eyes of the world will be on this game as usual, and I'm confident our supporters will do the club proud.
"Our fans are the best in the world and we want you to show your passion for the club, but in the right way. The derby is one of the most anticipated and exciting games in world football.
"The home support is so important for us, and I know they will be like an extra man for the team on the day. As always, we need our fans in full voice, but we also need them to respect the occasion."
Police are said to be taking extra security measures for the encounter.