Fast bowler Mitchell Johnson is firmly in the frame to make his return to the Australian squad for Perth after 12 months in the test wilderness.
Firebrand James Pattinson is in significant doubt for the third test after suffering side pain in Adelaide, and if the 22-year-old is ruled out Johnson is a prime candidate to make his return to the squad.
Johnson last pulled on the baggy green when he led Australia to a famous win over South Africa in Johannesburg in November 2011.
His heroics on that day were with the bat when he scored an unbeaten 40, but Johnson is hopeful of playing a key role with his left-arm pace on his home wicket the WACA.
Johnson was on the verge of being dropped following the tour to South Africa, but suffered a serious toe injury which sidelined him for all of last summer.
Chairman of selectors John Inverarity said following the first test in Brisbane that Johnson was being watched closely.
Australia were 5-111 heading into day four of the second test at Adelaide Oval, leading South Africa by 273 runs with five wickets in hand.
NSW quick Mitchell Starc would likely fill Pattinson's place in the XI, but Johnson could be picked in the squad and be an option if captain Michael Clarke decides to do without a spinner in the match starting next Friday.
Pattinson should find out the results of scans today, but the news doesn't look good.
The Victorian was forced from the field on day three and will almost certainly be absent from the attack for the final innings in Adelaide.
To back up for Perth in three days would be a big task and if the news is bad enough, he could well be scratched from the rest of the summer.
Pattinson would be a huge loss on the pace friendly WACA wicket, especially given Australia might be playing for the No 1 ranking in test cricket if they win in Adelaide.
It's been a test for injuries.
South African allrounder Jacques Kallis is set to miss Perth despite bravely batting on for his side on Saturday.
Proteas paceman Vernon Philander should play at the WACA, but was ruled out of the second test before it started because of a back spasm.
Johnson has taken 190 test wickets for Australia at 31.29, and has been in solid domestic form taking several three-wicket hauls in Shield and one-day cup games.
Fellow WA quick Nathan Coulter-Nile, rising NSW paceman Josh Hazlewood and Victorian allrounder John Hastings would also come into contention for a call-up to the national squad if Pattinson is ruled out.
Another test discard Phil Hughes also continued to remind selectors of his class after posting 127no for South Australia in a Shield game against Victoria on Saturday.
His timing is good with Rob Quiney's position looking doubtful after making just nine runs in three innings while Ricky Ponting's spot is also under threat.
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