World Cup winner Johann Muller and star flank Heinrich Brüssow were included in the Springbok squad for the away leg of the Tri-Nations series on Friday.

The pair have responded well to treatment and will be part of a 28-man party to take on Australia in Sydney on July 23 and New Zealand in Wellington a week later.

The squad includes World Cup-winning prop, CJ van der Linde, who was added as cover at the start of the week because of a number of injuries to leading front row forwards.

The 30-year-old Western Province prop - who can play on either side of the scrum - has now been retained having trained well with the squad this week.

"Johann and Heinrich are very important to us this year and they'll continue their rehabilitation on tour," said Peter de Villiers, Springbok coach.

"This squad is a good blend of experienced players, with World Cup titles behind their name, and the form players from Super Rugby, with some outstanding potential. We've had some good field session this week and I'm excited about this tour.

"We've chosen from our World Cup preliminary squad - so the players know they're in the selectors' thinking for the tournament. I've told them that this is their chance to prove that they're ready to take their place in the final squad."

Following the overseas leg of the Series, the Springboks host Australia in Durban on August 13 before concluding the shortened series against New Zealand in Port Elizabeth on August 20.

The final World Cup squad will be named on August 23.

South African tour squad:

Backs: Gio Aplon, Bjorn Basson, Juan de Jongh, Adrian Jacobs, Elton Jantjies, Patrick Lambie, Charl McLeod, Lwazi Mvovo, Odwa Ndungane, Wynand Olivier, Ruan Pienaar, Morné Steyn.

Forwards: Heinrich Brüssow, Jean Deysel, Dean Greyling, Alistair Hargreaves, Ryan Kankowski, Werner Kruger, Ashley Johnson, Johann Muller, Coenie Oosthuizen, Chiliboy Ralepelle, Danie Rossouw, John Smit (captain), Deon Stegmann, Adriaan Strauss, CJ van der Linde, Flip van der Merwe.