Australia batter Steve Smith has been ruled out of the third Ashes Test in Adelaide through illness.
Smith, who captained the hosts to victory in the first two Tests, was named in his side's XI on the eve of the match but withdrew on Wednesday morning.
His omission was confirmed by Pat Cummins, returning to lead the side after a back injury, with Usman Khawaja recalled in Smith's absence.
Khawaja, who turns 39 on day two, looked to have played his final Test for Australia after being left out but has been given an unexpected chance to prove his worth.
He was carded to bat in Smith's slot at number four rather than his usual opening position, with Travis Head and Jake Weatherald continuing at the top of the order.
Australia's rejigged batting card will be put to the test early after Cummins won the toss and invited England to field.
A statement from Cricket Australia confirmed Smith was suffering from a "potential vestibular issue", indicating problems with balance.
It read: "Steve Smith was ruled out of the third Ashes test in Adelaide today. Over the past few days he has been feeling unwell, with symptoms including nausea and dizziness.
"He was assessed and monitored closely and was close to being available to play. However, given the persistence of symptoms, a decision was made not to proceed.
"He is being treated for a potential vestibular issue. This is something Steve has experienced intermittently in the past and is being managed accordingly. He is expected to be available for the Boxing Day test in Melbourne."
