Australia's pace spearhead Peter Siddle says he's confident of overcoming lingering exhaustion and being fit to play in the decisive third test against South Africa starting Friday in Perth.
South Africa quick Dale Steyn, meanwhile, is just as eager to bowl the tourists to victory and notch what would be just the second South African series win in Australia.
Siddle has been recovering from a marathon 33-over bowling effort in intense heat in the fourth innings of the drawn second test and will not bowl in the nets until Thursday. On Wednesday he his body was responding well and he is confident he will be ready to play at the pace-friendly WACA Ground.
The 28-year-old said his bowling spell Monday was one of the toughest experiences of his test career.
"It was very dry heat out on the field which was tough work and a lot of overs ... just a bit of exhaustion and fight trying to get those last couple of wickets," Siddle said.
Faf du Plessis weathered Australia's bowling attack throughout the final day of the second test to score an unbeaten maiden century and help South Africa salvage a draw. South Africa will retain its No.1 test ranking if it draws the third test at Perth.
Despite Australia's official policy of rotating its fast bowlers to ensure adequate recovery time and avoid burnout, the loss of paceman James Pattinson for the season with a side strain makes Siddle's fitness for the third test vital.
"Last couple of days I'll just take it easy and get ready tomorrow and prepare then. I feel good, I've got plenty of sleep and the body is feeling good which is nice," Siddle said. "I woke up feeling good this morning ... so I'll have a bit of a trundle tomorrow and see how we go there."
The loss of Pattinson midway through the second test also provides a reminder of the dangers of pushing a body too far.
"I don't want to miss any test matches ... but I've still got to think of the end result," said Siddle, who says he expects to have final say on his fitness and doesn't anticipate selectors enforcing the rotation policy on him without consultation.
"I'm feeling good now, I've recovered well ... but if I'm struggling through tomorrow or if I don't feel 100 percent I've got to talk to the captain, the selectors and work out what's best."
Steyn, the ICC's top-ranked test bowler, says South Africa is determined to win the test, the series and retain its top test ranking, and he wants to be the man who makes it happen.
"We didn't come down to Australia to draw," Steyn said. "Australia has thrown everything they can at us and they still haven't beaten us.
"If we can play to what our potential is we're going to go home 1-0, and that would be fantastic."
Steyn has claimed just five wickets at an average of 51.6 this series, well below his career figures of 292 wickets at 23.98 each. But he is determined to boost his personal performance when it matters most.
"I always pride myself on standing up and doing something when we really need it and hopefully in this game something like that can happen," he said. "There's a bit more want, a bit more need. It all boils down to the last five days, and that extra push.
"I'll do everything I can in this game to try and get a result and get the wickets to win this test match."
Australia played four quicks in last year's thrashing of India at Perth, and selectors have that option again with Mitchell Starc, Mitchell Johnson, John Hastings and Josh Hazlewood all picked in the squad.
Siddle said Johnson had fitted back in into the side well after 12 months out of test cricket.
"We've spent a lot of time together and played a lot of cricket together so it's nice to have him back around the group," Siddle said. "My (Victoria) teammate John Hastings and young Josh Hazlewood is back in the group - so it's a good group of guys."