Factfile on sudden deaths in football following the death of Livorno midfielder Piermario Morosini from a suspected heart attack on Saturday:
The Cameroon midfielder died after collapsing during a Confederations Cup semifinal against Colombia in Lyon in June 2003.
The 28-year-old, who played for West Ham United, Manchester City and Lyon, fell to the ground unchallenged and was treated on the pitch before being stretchered off and receiving further treatment, including mouth-to-mouth resuscitation and extra oxygen.
Medical staff tried to restart his heart for 45 minutes but without success.
Benfica's Hungarian international striker collapsed during a Portuguese league match against Vitoria Guimaraes in January 2004.
The 24-year-old never regained consciousness and the autopsy revealed he had suffered from a heart defect.
The 30-year-old Brazilian defender collapsed during a first division match between his club Sao Caetano and Sao Paulo in Brazil in October 2004 and later died.
The Spain defender died after suffering a heart attack in his club side Sevilla's 4-1 win against Getafe in August 2007.
The 22-year-old collapsed in the first half, with medics preventing him from swallowing his tongue. But he collapsed again after going off and was given cardiac resuscitation before being taken to hospital.
He was placed in intensive care and his condition worsened before he died three days later.
The Motherwell captain died after collapsing towards the end of his side's 5-3 Scottish Premier League win over Dundee United in December 2007.
The 35-year-old midfielder fell to the ground just as he was about to be substituted and was treated for around five minutes on the field before being taken to a waiting ambulance.
O'Donnnell played for Scotland, Celtic and Sheffield Wednesday during his career.