Cape Town - Former Springbok centre Marius Joubert is not convinced that the national team’s centre partnership is a settled one.

In 2018, Bok coach Rassie Erasmus has used three different centre combinations in five Tests, with all of Andre Esterhuizen, Lukhanyo Am, Jesse Kriel, Damian de Allende used in midfield.

Esterhuizen and Am started in midfield in last Saturday’s 34-21 Rugby Championship win over Argentina but Joubert is not sure whether they are the right combination with next year’s Rugby World Cup in mind.

“Am is a good player but he makes mistakes on defence. Andre is a good ball carrier. I believe we should use Jesse Kriel at outside centre,” Joubert said in an interview with Netwerk24.

Joubert, who played 30 Tests for the Boks between 2001 and 2005 and formed a formidable centre pairing with De Wet Barry, said no centre has so far stood out to “make the jerseys their won”.

Joubert said Erasmus should also look outside the current group and mentionedthree players he'd like to see get a chance.

“Jan Serfontein is a guy who can make an impact if he’s fit. I’d also like to see Frans Steyn again. If he’s healthy and is added to the squad with the right mentality he can make a big difference. I also have high regard for Harold Vorster of the Lions but I’m not sure if he’ll get a chance.”

Serfontein and Steyn both play for French club Montpellier.

Erasmus, meanwhile, will announce his team for Saturday's Test against Argentina in Mendoza at 13:00 on Thursday.

Esternhuizen and Am are expected to remain as the starting centre pair.