Wallabies flank Rocky Elsom is in a race against time to be fit to take on the Springboks in the first of back-to-back Tri-Nations Tests in Durban on 23 August.

Wallaby coach Robbie Deans will finalise his 28-man squad, to travel to South Africa for the Tri-Nations encounters on Thursday.

Following the Round Seven match between South Africa and Australia in Durban, the two teams then head up to Johannesburg for the next match a week later.

A 30-man squad will assemble in Sydney for a two-day training camp, before heading to South Africa on Friday.

Based on injury assessments during the camp Deans will then finalise the 28 players to travel to the Republic.

The two injury concerns are the star flank, Elsom, and fullback Adam Ashley-Cooper.

Elsom missed the 10-39 Round Five loss to the All Blacks in Auckland just over a week ago, with a ligament strain in his left foot, while Ashley-Cooper, who scored the Wallabies' only try, had surgery last Tuesday on the hand he broke in the Test.

At the time it seemed highly unlikely that Ashley-Cooper would be fit to play in South Africa, but the hard-running fullback is desperate to get on the plane with the rest of his team-mates.

Western Force utility back Drew Mitchell could be used at fullback should Ashley-Cooper not be fit for the first South African Test. The other obvious option, Cameron Shepherd, is recovering from a broken leg, sustained against France in Brisbane.

Both Elsom and Ashley-Cooper are adamant they will be fit for at least the second Test in Johannesburg, but the final decision on whether the duo will tour lies with Deans.

The Springboks, who tuned up for their home leg of the Tri-Nations with a 63-9 (nine tries to nil) hammering of World Cup semifinalists Argentina last Saturday, play New Zealand in Cape Town on Saturday with the Tri-Nations title race still wide open.

The All Blacks top the table on 10 points, however, New Zealand have played one more game than both the Wallabies (second on nine points) and South Africa (five points).