Australia batsman Steve Smith has issued a warning to the West Indies and South Africa, saying he feels in the best form with the bat in six years.

The former captain scored an unbeaten 80 from 78 balls against England at Adelaide Oval on Thursday as Australia took a 1-0 lead in the three-match ODI series.

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Australia host the West Indies and South Africa in Test series over the home summer and will be buoyed by the confidence of their top batsman.

"(It) was probably the best I've felt in about six years," Smith told reporters on Friday.

"I was just in really nice positions and I felt really good, I honestly haven't felt that way in six years or so.

"It's been nice to score some runs in that time and we're always looking for perfection, and for me (Thursday) was as close to perfection as I will get."

Smith scored four runs against Afghanistan in his only innings during Australia's ill-fated T20 World Cup title defence.

However, he has been on fire in one-day cricket, scoring 105 and 61 in his previous two innings against New Zealand in Cairns.

He will hope to convert that form into the longest format when Australia meet West Indies in Perth for the first test starting Nov. 30.

Smith has a stratospheric career average of 60 in 87 Tests, though he has averaged 44.47 over the last two years.

The batsman said England, who they play again in Sydney on Saturday, may not have been at their sharpest at Adelaide Oval just a few days after celebrating their T20 World Cup triumph in Melbourne on Sunday.

"I don't doubt they were sporting a few hangovers - and as you should after winning a World Cup," he said.

"I saw some (England) boys who were staying at the same hotel. There were some tired-looking boys there, a bit glassy-eyed.

"But you can't take any series for granted ... and hopefully we can wrap (the series) up in Sydney."