Leg spinner Warne said South Africa's performance in the first Test in Cape Town, which Australia won by seven wickets inside three days, did nothing to make him revise his low opinion of the home side.
The teams will clash again in the second Test in Durban on Friday.
The South African team management asked the groundsman in Cape Town to water the pitch in an apparent attempt to negate the threat posed by Warne, who is most lethal on drier surfaces.
The move backfired when seamer Stuart Clark took nine for 89 on a pitch that consistently offered movement off the seam.
''You are already winning, aren't you, before you even bowl a ball,'' Warne told a news conference.
''That just shows you the state of the South African mind.
''If they are telling groundsmen to water it then we've got a psychological advantage straight away. You can't write a better script than that.'' Warne said the Australians would welcome a repetition of South Africa's pitch experiment on Durban's traditionally seam-friendly pitch.
''If that's their mindset here, if they want a green thing that's going to seam all around the place ... I think the same result will happen,'' Warne said.
''If they want to juice it up to negate me, I'll take my nought for 40 and we win in three days.
Warne repeated the suggestion he made before the series started that the team was among the poorest Test sides South Africa had produced.
''They were probably the worst performing South African team that went to Australia (earlier this season),'' Warne said.
''I think the way they fought back in the One-day series was a credit to them, to chase 435 (to win the deciding One-day international) was just an amazing effort.
''But in the Test arena it's a different story.
''When the ball starts to seam it exposes a few techniques, and their middle order is getting exposed because they are one or two down early all the time.'' South African all rounder Jacques Kallis smiled broadly when he was told of Warne's assertions.
''The guys realise he's there for entertainment,'' Kallis said at another news conference.
''He always comes up with statements and the guys don't take them too seriously.
''It's a laugh or two in the change room.''