Usman Khawaja reveals bombshell diagnosis

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Nine months after retiring from international cricket, Usman Khawaja has revealed he lived with rheumatoid arthritis throughout his 88-Test career and at one stage feared he "was going to die".

In an extraordinary interview with the ABC, Khawaja said he was diagnosed with the disease when he was 22-years-old and was initially convinced he had contracted a terminal illness.

It was a diagnosis Khawaja not only kept from the public and cricket fans, but also his nearest and dearest teammates. Only the medical team and coaching staff were aware.

"I genuinely thought I was going to die," the 39-year-old told Australian Story. "I went from this athlete who was playing professional cricket to not being able to walk 10 metres to the bathroom."

Khawaja, who scored 6,229 Test runs including 16 centuries for Australia details his experience of living with an autoimmune disease in his autobiography Sabr.

Hoping he can give confidence to others, he writes: "If a person can play at the top level … as a professional cricketer with rheumatoid arthritis, then I think a lot of other people can achieve a lot, too.

He also puts his incredible success down to a "god-send" of injections that helped him be fit enough to take to the field.

"Without that drug I would never have played cricket ever again or even lived a normal life again," he writes.

Despite retiring from the international scenes, Khawaja remains involved in the sport and recently suggested there were up to five Aussies performing well enough to replace Marnus Labuschagne whose spot in the team is again under scrutiny.

It's been 47 innings since Labuschagne scored a hundred with his most recent results in South Africa 37, 37, 14 and 39.

“We've got plenty of players in Sheffield Shield cricket who are very good players, who are pretty much averaging and doing the same as Marnus in that respect,” Khawaja said.

“You've got Kurtis Patterson right now who is scoring the house down. Marnus averages 38 in Sheffield Shield cricket, Kurtis is about 39. He's just scored a hundred, he's been scoring runs the other day.

“Peter Handscomb, 39 (average), terrific player. Cameron Bancroft, only 32 years old, also at 38 (average). You have Marcus Harris as well. These are all Test players.

"Jack Clayton, who is a young guy that I played with. He’s scored six centuries averaging 38 and no one talks about him.”

"So the narrative of when people devalue Shield cricket, it frustrates me because I'm like, OK, if Marnus is good enough to play for Australia with that Sheffield Shield record, why can't any of these guys play?"

The third Test between South Africa and Australia in Cape Town starts on Tuesday night AEDT.