Cartwright replaces struggling batsman Nic Maddinson at No. 6 and left-arm spinner Steven O'Keefe replaces paceman Jackson Bird in the two changes to the XI which beat South Africa in Adelaide and then won the first two tests against Pakistan.

"We're playing the two spinners, traditionally out here it does take some spin," Australia skipper Steve Smith told a news conference Monday, on the eve of the third test. Bird "bowled particularly well in Melbourne, but conditions sometimes change the team."

Australia started the series with an attack featuring three fast bowlers and off-spinner Nathan Lyon in victories at Brisbane and Melbourne, but needed to add an allrounder to get runs in the middle order and to provide seam bowling backup for pacemen Mitch Starc and Josh Hazlewood following the inclusion of a second spinner on a wicket that does turn.

Cartwright, 24, has played 16 first-class matches since his debut for Western Australia in 2013, averaging 44.5 with the bat and with his 15 wickets coming at an average of 41.93.

Smith said Cartwright's medium pace bowling had improved over the last year, gaining 10 kph in speed, and he was bowling with more consistency.

O'Keefe will play his fourth test, getting the second spinning spot in favor of 23-year-old Ashton Agar.

Australia has won three tests since overhauling the team following a five-test losing streak.

"Things have gone pretty smoothly since then. It was a pretty difficult time," said Smith, who will be playing his 50th test. "Since we made a few changes and got some new guys in, I sort of felt a shift in energy and enthusiasm.

"I've been really proud of the way we've played."

Misbah-ul-Haq is expected to remain captain for Pakistan in Sydney, despite speculating about retirement following the innings defeat in Melbourne last week.

The 42-year-old Misbah has posted scores of 4,5, 11 and 0 in his four innings so far in the series. He was out for a second-ball duck, attempting a premeditated sweep shot to Lyon, when Pakistan needed to bat out two sessions to salvage a draw in Melbourne after conceding a 181-run first-innings lead to the Australians.

Australia: David Warner, Matt Renshaw, Usman Khawaja, Steve Smith (captain), Peter Handscomb, Matthew Wade, Hilton Cartwright, Mitchell Starc, Steve O'Keefe, Josh Hazlewood, Nathan Lyon.