Report from BBC Wales.
 Terry Coles died in May 2000 |
An investigation is under way after the message about Terry Coles's death was shown on the giant screen during the Cardiff-QPR play-off at the Millennium Stadium last Sunday.
Mr Coles, a Swansea City fan, was accidentally kicked to death by a police horse at a game in Rotherham in May 2000.
The message appeared after being submitted - alongside genuine goodwill messages - via a mobile phone to staff operating the big screen.
Although some messages are rejected, the 'sick' taunt got through because workers did not understand the reference it contained.
The message also mentioned former star Alan Davies, who committed suicide while a Swansea player.
His widow Christine, 55, said she was appalled by the text message.
"It's horrible - they're obviously sick," she said.
"They are just sad and I'm not going to let it affect me."
Cardiff City Chief Executive David Temme said he was disgusted by the incident.
 Andy Campbell scored during the play-off match |
"No Cardiff City supporter or anyone with contacts in football would be connected with such a vile and offensive statement," he said.
The Football League say they are deeply sorry for any offence caused, and have offered to help police find the people responsible.
"We know the number the text was sent from and we will co-operate with any police inquiry," said a spokesperson.
Father-of-two Mr Coles, 41, was fatally injured as visiting supporters were ushered into turnstiles in Rotherham.
Marilyn Croft, spokesperson for the Swansea Supporters Trust, called for the person responsible to be dealt with.
"I think is is absolutely moronic - it is a cruel thing to have happened," she said.
"It must have been some very sick individual to have done something like this."