South African superstar Jacques Kallis may be playing his last Test in Australia after aggravating his hamstring injury during a gallant innings.
Kallis will not be fit for the series-deciding third Test in Perth starting next Friday, with the Proteas to send for a replacement batsman.
The 37-year-old defied his torn right hamstring, and Australia's bowlers, for nearly two hours in making 58 on Saturday's third day of the Adelaide Test.
Frequently grimacing in pain, Kallis will bat again in the second innings in what could be his last Test appearance in Australia.
"It's unlikely he will respond in time to be fit to take his place for the Perth Test match because we have got a quick turnaround," South Africa's team doctor, Dr Mohammed Moosajee, told reporters.
"Selectors are considering who to send over as cover."
Kallis, batting an number nine, was in great discomfort during his courageous knock.
The 37-year-old strolled between the wickets and leant on his bat for support numerous times during breaks in play.
His pain was never more obvious when ducking to avoid a series of short balls from Australia's fast bowlers, instinctively reaching with his hand for the torn muscle after ducking.
"We knew he was always able to bat, the challenge was what is going to happen," Dr Moosajee said.
"Safe to say that he probably aggravated his injury by running and batting.
"Every time he stretches forward or he ducks under a bouncer or takes off or stretches or lunges forward, he is straining that area particularly."
Kallis tore the hamstring while running in to bowl during Australia's first innings on Thursday.
The 157-Test veteran will become the second South African batsman ruled out of the Australian tour, after JP Duminy ruptured an Achilles tendon in a freak injury during the first Test in Brisbane.
Duminy will miss six months of cricket, having collapsed during a warm-down after the opening day of the Brisbane Test.