McKenzie has also revealed out-of-favour prop Benn Robinson is in selection contention and that he has spoken with giant lock Sitaleki Timani about staying in Australian rugby next year.

The Wallabies ended a four-Test losing steak when they narrowly avoided a shock loss to Argentina in Perth last weekend.

The 14-13 triumph - McKenzie's first win as coach - will give the team a much-needed confidence boost and they could be bolstered further if Horwill is fit to tour.

The second-rower has missed the past two Rugby Championship matches with a hamstring injury.

Ben Mowen captained the Wallabies in their one-point win over Argentina and McKenzie refused to speculate on who would be the team's skipper against South Africa in Cape Town on September 29.

When asked if Horwill was an automatic selection as captain if fit, McKenzie said: ''I haven't thought about that. I'll work out where he's up to on injury and see if he's fit enough to join the group first.

''There's no evidence to say [Horwill] wouldn't be fit by the weekend. We haven't been carrying a rehab program at all.

''I think James would know he has to be right to train 100 per cent on Saturday. That's what we'll look at and we'll work it out. I think he is tracking well.''

The Wallabies were desperate to beat Argentina after a horror start to McKenzie's tenure as coach and winning just one of their first six Tests this year.

The players will be given a week to recuperate before gathering in Sydney at the weekend and flying to South Africa. The Wallabies will also play Argentina in Rosario on October 6.

Timani made his international return against the Pumas in Perth after initially being overlooked for a spot in McKenzie's squad.

He has a contract to play in France next season and McKenzie wants to invest in players who will be in Australia.

But injuries opened the door for Timani to join the squad and if the ARU does not release him by the start of October, it could jeopardise his $2.4 million deal with Montpellier. Timani said last week that he wanted to play overseas even if the Montpellier deal fell through.

He added power and physicality to the Wallabies' forward pack when he came on in the second half against Argentina and McKenzie has spoken to the 203-centimetre, 120-kilogram player about his future.

''We've been investing in guys who are going to be around but some of those have dried up through injury,'' McKenzie said.

''At this point in time, it's finite - but he's definitely a handy asset. I've met with him.

''I know all the players are trying to work him over to find out what he's doing because there's some conjecture about where he's going to be.

''He's signed a contract to play somewhere else. If that changes, our outlook changes. The ball's in his court. I've already said that if he was staying around, it's very different from my point of view.''

Robinson, a 59-Test front-rower, was the highest-profile axing from McKenzie's initial squad last month.

But with the scrum under pressure and struggling for consistency, Robinson is back in selection calculations after playing in the Shute Shield grand final at the weekend.

''We've thought about [Robinson] all the time,'' McKenzie said. ''We know what he's capable of and has a lot of experience so he's never out of your thinking.

''It's just a question of the guys you've got and whether you're happy with how they're travelling. [The scrum] is going in waves, it's not as consistent as we would like.''