Steve Smith will captain Australia in the fourth and final Test against India starting on Thursday as regular captain Pat Cummins remains in Sydney with his family, Cricket Australia (CA) said on Monday.
Cummins returned home after the second Test in New Delhi to be with his ailing mother after Australia had dropped 2-0 behind in the four-Test series for the Border-Gavaskar Trophy.
Smith led their turnaround in Indore where they beat India by nine wickets inside three days to secure their place in the final of the World Test Championship in June.
"Pat Cummins has been ruled out of the fourth Test match against India in Ahmedabad to remain in Australia with his family," a CA spokesperson said.
"Steve Smith will captain Australia in the final Test match of the series."
Smith led Australia between 2014 and 2018 before he was stripped off the honour following a ball-tampering scandal in South Africa.
But he has been Cummins's deputy since the paceman became Test captain in November 2021 and has stepped in three times to lead Australia in that time.
Smith said last week he had no ambition to return as full-time captain at any stage.
Meanwhile, CA added that Nathan Ellis would replace Jhye Richardson, who has a hamstring injury, in the squad for three one-day internationals that follow the Test series.