"It's hard to split Virat Kohli and Smith for the title of No.1 Test batsmen in the world at the moment and the best players like the battle and are super competitive." Warne was quoted as saying by cricket.com.au.
Warne also warned the English that they should sledge Smith only at their own peril.
If I was England the best thing now would be to not say a word to him when he walks out, just ignore him and give him the silent treatment.
"Engaging him in banter could just ignite the concentration within and lead to a big hundred for the Aussie skipper.
"It's a bit like when the Australian teams that I played in started sledging Brian Lara – we learnt after the seventh or eighth ton that it wasn't a great plan."
Warne also explained what sledging meant to him.
"For mine, the art of sledging is all about unsettling your opponent to the point where they lose concentration and focus," he explained.
"It's about being subtle, clever and humorous rather than loud bravado. It's the little word here or there, often when your opponent least expects it, that can really touch a nerve.
"Sledging is about making a batsman think of something other than what he should be.
"Taking an example from another sport, it's like arriving at a par three with a green protected by water and recalling to your partner about the time he 'sliced one into the drink on the right'. (It) just gets you thinking.
"Joe Root? The Aussies in Perth on Thursday might chat to him about his issues with turning fifties into hundreds. That and how his side is 'massively still in this series', as he said on Wednesday night."
First Published: December 9, 2017, 10:41 AM IST