The telltale sign Souths great Nathan Merritt was struggling with a serious illness before he ended up fighting for his life in hospital

Footy star turned boxing great Anthony Mundine has claimed former Rabbitohs winger Nathan Merritt was battling a serious illness before suffering an adverse reaction to painkillers that nearly killed him.

Merritt, 40, is still fighting for his life in a Sydney hospital – and the man affectionately known as ‘Choc’ claims the prolific goalscorer also had a bout of pneumonia before collapsing at his aunt’s house.

“He didn’t know he had it,” Mundine told him Daily Telegraph.

“He kept asking for his puffer every 10 minutes (at the last Koori Knockout tournament on the NSW Central Coast) because he was having trouble breathing.”

Merritt was found unresponsive last Friday and has been on life support at Sydney’s Royal Prince Alfred Hospital ever since.

Boxing great Anthony Mundine has revealed former Rabbitohs star Nathan Merritt was battling a serious illness before being hospitalized and put on life support.

Merritt, 40, is still fighting for his life in a Sydney hospital – and the man affectionately known as ‘Choc’ said the prolific goalscorer also had a bout of pneumonia.

On Tuesday, his family released an update, confirming the former NRL star’s condition had improved ‘slightly’.

Merritt’s sister, Teanne, said he was still in critical condition.

But she warned that her brother is not out of the woods yet and has a challenging journey ahead of him.

Visitors to the hospital, apart from immediate family and close friends such as Mundine and Bulldogs winger Josh Addo-Carr, remain off limits.

“We have been advised that Nathan is improving a little, but he has a long road to recovery,” Teanne posted on Facebook.

“Thank you to everyone, family and friends who have come to visit Nathan and all the well wishes and kind words from everyone. ‘Thank you all for your continued love and support.’

It comes after the Rabbitohs finally broke their silence on Merritt’s situation five days after he was rushed to hospital.

“Out of respect for the privacy of Nathan and the Merritt family, the Rabbitohs and Souths Cares have chosen not to comment on his situation at this time,” the club said in a statement.

“We are very happy to hear directly from his immediate family that Merro’s condition is improving.

“He is being looked after by the best doctors and he is in the thoughts of everyone connected with the Rabbitohs.

“It will be a slow recovery but it is a battle he is in with all our support. Keep fighting hard with that South Sydney soul, Get it! You are always a Rabbitoh! #974′.

Merritt, who hung up his boots in 2014 after 237 first-grade games, is regarded as one of the greatest players in the club’s history.

Born and raised in Redfern, he began his football journey as a junior player with Alexandria Rovers in the South Sydney junior competition.

After retirement, the father of five channeled his passion for sport into a cause close to his heart, founding the Nathan Merritt Foundation dedicated to providing guidance and support to Indigenous youth in Sydney.

Lifeline 13 11 14; beyond blue 1300 22 4636; 13 THREADS 13 92 76; Aboriginal Counseling Services 0410 539 905