Shami has takesn nine wickets in the series so far and is the second-highest wicket-taker behind Vernon Philander.

"When you are bowling in South Africa, it is important to have that away-swinging line. Shami has that. Hardik Pandya has that too, but he doesn't have too much pace. Until he gets that pace he will not be a big wicket-taker.

"He will fit into India's overseas plans very well though, because he bowls that away-swinging line. Bhuvneshwar Kumar also has that, but he didn't play in Centurion," he said.

Skipper Virat Kohli attracted lot of flaw for dropping Bhuvneshwar Kumar and de Villiers said that Kohli's tendency of constant chopping and changing has surprised him.

"I am genuinely surprised that Kumar didn't play. He should be playing all overseas Test matches for India. He is someone who can take the ball away from right-handers and then bring it back into left-handers as well.

"That is the future of world cricket on quicker wickets and this has been the past. Jasprit Bumrah bowled well, but he primarily bowls into the right-hander, or bowls into the stumps. Even on flat wickets like Centurion, Kumar can average 4 wickets per match. It was a big mistake not picking him," said de Villiers.

"Ishant Sharma bowls into the stumps. Bumrah bowls into the stumps too. In South Africa, you cannot have two pacers bowling into the batsmen on a wicket like this. Bumrah bowled well in patches yes, but is he going to take 8-9 wickets in a Test? How many times has Ishant picked 8-9 wickets in a Test?

"He cannot, because he bowls an incoming delivery into the bat. Kumar can do it, Shami can do it, and they have done it before if I am not mistaken, because they have the away going delivery. So, Shami is your future, Kumar is your future, and they bowl quick enough to be in that category.

Even Pandya is your future (if he adds a little pace)."

De Villiers who was a part of the touring side under late Hansie Cronje when South Africa lost 1-2 in Tests, wasn't too pleased with India opting out of practice matches.

"No traveling team is doing well nowadays. Even one match is not enough. You need to play 3, 4 or even 5 practice matches, like during old English tours when you played different counties, and then play the first Test.

"It doesn't happen these days with packed calendars. If you play one practice match, are you really going to pick up everything in 2-3 days? It is very difficult so you need to spend a good 2-3 weeks in South Africa, or wherever else you go, especially if you are a sub-continental team traveling overseas. That might make a difference later," he said.

The former pacer feels switching from one-day mode to Tests is the biggest challenge for the Indian team.

"The biggest problem with Indian batsmen is how much ODI and T20 cricket they play, not conditions. They need to detox from limited-overs' cricket and start getting into Test mode.

"You need to be conservative for that. You want to play your shots, fine, but a little extra bounce will get you out. Look at how Faf du Plessis batted at Centurion.

"He started off with 40-50 strike-rate, and then as he batted longer, he reduced it to 30-35 strike-rate. He becomes conservative on such pitches because one ball can get you out. No Indian batsman, except Virat, did that," he added.

De Villiers further predicted that it will be difficult for India to avoid a 3-0 whitewash as the Wanderers wicket would assist pace.

"They had their chance at Centurion. It was a wicket tailor-made for India, not South Africa. I don't think Wanderers will be a friendlier wicket than that."

"The conditions will once again be different and the only chance is if Indian batsmen reel themselves in and play more conservatively to stay-in at the crease. In India, once you get in, you become flamboyant and play lots of shots.

"In these conditions, you will get out playing too many shots. In India you don't get out, and the way they are playing now, if they play 10 Tests overseas, they will lose 9 out of 10. I expect better from the World no.1 Test side," he signed off.