Former Rabbitoh's winger Nathan Meritt remains on life support after being admitted to Royal Price Alfred Hospital in Sydney on Friday.
According to the Daily Telegraph, the 40-year-old had an adverse reaction to prescribed pain medication.
Merritt's sister Teanne posted a serious but hopeful update to Facebook last weekend.
"On behalf of Nathan and our family, we would like to thank everyone for your well wishes and prayers," she wrote on Saturday.
"Nathan is still in a critical condition but he’s a fighter and we are grateful for everyone's support through this tough time. We will update you when we can."
On Tuesday, Teanne said that she has been advised that Nathan is improving slightly but has a long road to recovery.
Merritt's former club confirmed the seriousness of his condition.
"Nathan is in the thoughts and prayers of every Rabbitoh at the moment," Souths CEO Blake Solly said on Saturday.
Merritt retired as one of the most infamous try-scorers in Rabbitohs history.
Some of his career highlights include playing one game for NSW State of Origin in 2013, two Australian Prime Minister's XIII appearances, two City Origin appearances as well as representing the NRL Indigenous All Stars three times.
He was awarded the Preston Campbell Medal for his man-of-the-match performance in the 2012 Indigenous All Stars game.
