The 54-year-old captained South Africa to their lone major post-apartheid football success, winning the 1996 Africa Cup of Nations.
South African football legend Neil Tovey was "slightly improved" Monday after suffering a heart attack the previous afternoon while training in Durban for a charity cycle race.
"Neil is slightly improved, but remains in a critical condition," said brother Mark, himself a former professional footballer.
"The doctors have been working round the clock. They are still ascertaining what the damage is to the heart muscle, his lungs and maybe the brain."
Centre-back Tovey, 54, captained South Africa to their lone major post-apartheid football success, winning the 1996 Africa Cup of Nations by defeating Tunisia 2-0 in the final in Soweto.
Pictures of the only white captain of a Cup of Nations-winning team receiving the trophy from then state president Nelson Mandela remain among the most iconic in South Africa sport since an international ban was lifted in 1992.
Tovey was capped 52 times, 29 as captain, and spent much of his playing career at Kaizer Chiefs, one of the most successful and popular football clubs in the republic.
He later coached several top-flight South African clubs and guided Mamelodi Sundowns to the 2005-2006 league title.
There has been huge social media support for Tovey with many tweets referring to him by his playing-days nickname Mokoko (proud male).
National labour umbrella body Cosatu wished "our captain" a speedy recovery.
Tovey suffered cardiac arrest last year while playing squash and soon after was appointed national technical director by the South African Football Association.