The 21-year-old's three-wicket haul set up a thumping 10-wicket demolition of India in the group phase, and Pakistan have not looked back, notching five consecutive wins to meet Australia in Thursday's semi-final in Dubai.

Finch and opening partner David Warner will be first to face the music against Afridi. Seeing off his first spell could prove decisive.

"The powerplay definitely holds the key," Finch told reporters.

"Shaheen has been in really good form for Pakistan. So that's going to be a crucial battle, no doubt."

Finch was happier to talk up Australia's quicks, admitting he was pleasantly surprised at how effective the three-prong attack of Mitchell Starc, Josh Hazlewood and Pat Cummins had proved on the United Arab Emirates pitches.

Hazlewood took four wickets to help Australia thrash West Indies to secure their semi-final berth, while Starc has seven wickets for the tournament.

"It's no secret. Our quicks have done a really good job," said Finch.

"With the new ball, Cummins, Starc and Hazlewood have been fantastic.

"We've been really happy about how they've executed and kept pressure on oppositions. They're a world class trio."

Beating Pakistan would put Australia within one win of claiming their first T20 title, a scenario that seemed far-fetched before the tournament with senior players out of form and lacking match fitness.

Finch said "everyone" had written Australia off but denied the team had used that as motivation.

"We didn't speak about it all, to be honest," he said.

"It's interesting how the narrative can change really quick.

"About 10 days ago, our team was too old and now we're an experienced team."