"Chief executive Alistair Mackintosh has this morning telephoned Portsmouth's chief executive Peter Storrie to enquire about Pedro's health. The two clubs share an excellent relationship and everyone at Manchester City, especially Ben himself, wishes him the very best."

Thatcher added: "Immediately after the game I tried to find out how Pedro was. I have written to him today apologising for what happened."

It is not the first time Thatcher has been guilty of reckless play. He was sent off for two bookings against Shanghai Shenhua during City’s summer tour to China, but it was an elbow that resulted in one of the Shanghai players suffering a collapsed lung during the same match that lingers in the memory.

And he received a two-match ban for elbowing Nicky Summerbee while playing for Wimbledon against Sunderland in January 2000. Worse still, the attack on Mendes was not his first of the game. He also raised arms at Sean Davis, Kanu and Benjani Mwaruwari, which escaped the attention of Gallagher.

Last month, midfielder Lee Bowyer pleaded guilty to Newcastle Magistrates Court for violating a section of the Public Order Act when he and then teammate Kieron Dyer clashed during Newcastle's 3-0 loss to Aston Villa in April 2005.

Bowyer admitted to using threatening behavior during the on-field fight, which ended with both men being sent off. Bowyer was fined £600 and ordered to pay costs of £1,000.

In 1995, Duncan Ferguson served 44 days in Barlinnie Prison after headbutting John McStay, of Raith Rovers, while playing for Glasgow Rangers. He became the first professional footballer to be jailed for an offence committed on the field.