Spectators at Lord's have been warned to desist from the time-honoured tradition of firing their champagne corks onto the field of play, because they risk causing a "hazard" to the players.

Lord's is the only international cricket ground at which spectators are still allowed to bring in their own alcohol, but in its latest newsletter, Marylebone Cricket Club admitted that concerns had been "formally raised" by visiting players who have been in the firing line.

"In recent times the practice of some members and other spectators opening bottles of champagne in such a way as to allow corks to be projected on to the outfield has been criticised," the letter read.

"Any items which are aimed at the playing area may cause a potential hazard to fieldsmen, and this point has been made formally to the club.

"Lord's is now the only ground into which members and ticket holders are allowed to bring alcohol, and in order for this arrangement to continue it is important that all members, their guests and other spectators refrain from the practice that has been described."