Wales will represent South Africa's "most difficult opponent" of the November Tests when they host the Springboks on Saturday, says Rassie Erasmus.
The Boks finish their four-match tour of Europe when they face Wales at the Principality Stadium in Cardiff, a venue where they have not won since 2013.
South Africa defeated Wales 24-15 on that occasion, but they have since lost three times in Cardiff and have lost three straight against the Dragons -- two in the principality and most recently in Washington D.C.
South Africa lost by a single point to England at Twickenham in their tour opener, since when they have defeated France in Paris, with a try in time added-on, Scotland in Edinburgh, but Erasmus was very clear on Monday when he the challenge that awaited the No. 5-ranked Springboks on Saturday. Wales are now No. 3 on the World Rugby rankings, behind only New Zealand and Ireland.
"In our view, Wales are definitely the most difficult opponent we will face on this tour," Erasmus, the Springboks head coach, said at a media conference.
"Warren [Gatland] has managed to build a superb side with lots of experience, and they are playing a good, balanced game, plus they have good depth and quality in their squad.
"They put Tonga away last weekend and the previous week they defeated Australia, so we are preparing ourselves for the most difficult Test of this tour."
Erasmus, meanwhile, said that Eben Etzebeth, the most experienced member of the tour squad, would be assessed on Tuesday afternoon to prove his fitness in order for him to be considered for selection.
Etzebeth sustained a foot injury in the Test against England at Twickenham, and he has since missed the matches against France and Scotland. "Last week I said it was a 50/50 [for Etzebeth to be ready]," Erasmus said.