Ryan Harris has hailed Aaron Finch's "outstanding" captaincy and believes Ricky Ponting helped the in-form Australia captain to "flick the switch" at the Cricket World Cup.

Finch was under pressure as he struggled due to a lack of runs against India at the start of this year, on the back of being axed from the Test side.

The opener showed his class in an ODI series whitewash of Pakistan in March and has lit up the World Cup, blasting two hundreds and three half-centuries at the top of the order for the holders in England.

Only opening partner David Warner has more than Finch's tally of 504 runs in the tournament, laying the foundations and leading his side superbly to the semi-finals with seven wins out of eight.

The defending champions are top with one group game remaining against South Africa and former Australia paceman Harris says the skipper should take huge credit.

Harris told Omnisport: "He's been pretty impressive for a while now. He's been through some pretty average times, form-wise, but you would not have known it.

"The way he has led the side has been outstanding, through good or bad he's able to do it very well.

"There were people calling for his head when he wasn't making a lot of runs against India and he's done a bit of work, flicked the switch and look where he is now - it's just amazing.

"He's done work with [Australia assistant coach] Ricky Ponting and it's great to see him get the rewards for what he has done and his captaincy has also been outstanding."

Harris also praised paceman Mitchell Starc, the leading wicket-taker in the competition with 24 dismissals after claiming outstanding figures of 5-26 in an 86-run drubbing of New Zealand at Lord's on Saturday.

"Starcy has copped a fair bit of criticism, about him not being able to do what he used to be able to do with a white ball, and he's answered that so well," Harris added.