Australia's Pat Cummins celebrates taking the wicket of Sri Lanka’s Nuwan Pradeep to win their World Cup match. Photo: Paul Childs/ Action Images

LONDON - Australia paceman Pat Cummins has fired a warning at the nation’s Cricket World Cup rivals, saying the champions may have “clicked” but are yet to put in a complete performance.

Aaron Finch’s Australia booked their place in the semi-finals early with a comprehensive win over England and carried on the form with another convincing victory over New Zealand at Lord’s on Saturday.

Australia will head into their final round robin match against already eliminated South Africa in Manchester on Saturday.

“I think just everything’s clicked, the batting, the bowling, our game plan is the way we’ve wanted to play,” Cummins told reporters.“Even just everyone being comfortable in their roles and comfortable around each other. I think it takes time but everyone’s in a really good place.

“The thing we have spoken about, we have managed to scrape home wins without really putting through a complete performance,” Cummins added.

“With each game, we have got a little bit better.”

Australia's Pat Cummins celebrates the wicket of England's Jonny Bairstow. Photo: Reuters/Peter Cziborra

Jason Behrendorff’s promotion to open the bowling with Mitchell Starc, with Cummins switched to first change bowler, has been key to the improvement.

Cummins has only nabbed one wicket from the last two matches but has proved highly effective at keeping the batsmen pinned down during the middle overs. He captured Ross Taylor’s wicket and conceded 14 runs from six overs against New Zealand.

The match against South Africa will be the first that opener David Warner and former skipper Steve Smith have had against Faf du Plessis’s side since they were suspended for ball-tampering during the Cape Town Test in March, 2018.

Warner and Smith’s one-year ban expired at the end of March. The former leads the tournament’s runs list with 516 and the latter has chipped in with 287.

Cummins did not feel the ball-tampering history would matter.

“I know Dave and Smithy have played quite a bit with (South Africa’s players) in IPL and played heaps of times before so I wouldn’t have thought so,” he said. 

Reuters