Niki Lauda's son Matthias says his father is "training with fury" as he continues his recuperation from a lung transplant and illness. The three-time world champion has spent much of the past eight months hospitalised after undergoing surgery to save his life.
Lauda had a lung transplant last year after falling ill while on holiday and doctors have previously revealed that the Austrian came mere days from dying, before he was operated on.
Lauda's immune system was weakened by his stay in hospital, while he remained too weak to visit grands prix in the latter half of last season, despite aiming to have returned at the Abu Dhabi GP.
A bout of flu over Christmas meant Lauda had to go back into intensive care, but he is once again at home, where a rehab regime described as "intensive" goes on.
Matthias told La Gazzetta dello Sport: "Dad has undergone a complex operation and has had bad moments, but he has a strong character and is fighting.
"He needs to do physiotherapy to recover his energies.
"He trains with fury and I hope that soon we will see him in shape.
"I speak to him every day. When I'm not there, with him there is my brother Lucas. One of us is still in Vienna."
Lauda had hoped to be present at the season-opening Australian Grand Prix, but it is unclear if his recent illness will impact that.