Cricket Australia on Tuesday called up fast bowler Scott Boland to the squad to face England in the potentially Ashes-clinching Boxing Day Test in Melbourne.
The Victorian quick had already been training with the side and will provide injury cover for a bowling attack that has torn through England's batting order to take a comfortable 2-0 lead in the five-match series.
Cricket Australia said he "joins the squad while the medical team assesses the fast bowling group following the second Test victory."
It was not clear which Australian bowler was at risk of missing the Melbourne Test, but Josh Hazlewood is racing to recover from a side strain, which forced him to miss the second Test in Adelaide.
Mitchell Starc at times appeared to struggle with a sore back during that match, but was able to complete 27 overs, taking two wickets for 43 runs in England's second innings.
Captain and world No 1 Pat Cummins was forced to drop out of the Adelaide Test when he was deemed a close contact of a Covid-positive restaurant diner, but he is expected to make a return in Melbourne.
Cricket Australia said Boland "has been in strong form for Victoria this summer with 15 wickets from two matches against New South Wales at an average of 10."
Similarly to Boland for the Melbourne Test, Jhye Richardson was brought in to the side in Adelaide in the absence of Hazlewood and Cummins and impressed with a five-wicket haul, although he is aware that might still not be enough to retain his place.
"The beauty of Australian cricket at the moment is we've got fast bowling stocks for days," Richardson, 25, said. "I think that's a wonderful problem for the selectors to have. Whatever happens, happens.
"I had an unfortunate first innings and then bowled a little bit better second innings. I'm happy to go either way. As long as we're winning, then that's all we can ask for."
Playing his first Test in nearly three years after a prolonged recovery from a shoulder problem, Richardson conceded that he had struggled to make the step up in England's first innings as he went for 78 runs without a wicket in 19 overs.
His ability to bowl straight and get the ball to skid along the deteriorating Adelaide surface played an integral role in ending a spirited English rearguard, though, and Richardson felt it might be effective late on in other Tests in the series.
"If my job is to hit the stumps, then that's what I'm going to try and do," he said. "Potentially being a little bit skiddier on wickets that are up-and-down, that may be an advantage.
"Somewhere like (Sydney Cricket Ground) as well could be an advantage on day four and five when it starts to go up-and-down," he added. "Having those variations in the team is very important."
The third Test in Melbourne starts on December 26.