MacGill picked up an injury during the first Test

Spinner Stuart MacGill is picked, subject to a fitness test after suffering a tear in his right calf on day three of the series opener in Perth.

But paceman Jason Gillespie misses out after tearing a left-side back muscle.

Batsman Darren Lehmann retains his place but is also a doubt with tendonitis in his left achilles.

Uncapped fast bowlers Brad Williams and Nathan Bracken earn their chance to impress.

Brad Hogg and Simon Katich also make the squad, which will again be lead by veteran Steve Waugh.

Australia's bowling stocks have been tested by an ankle injury to paceman Glenn McGrath, who had surgery last week and was ruled out of the series.

Williams could make his Test debut in Sydney

"Injuries have forced us to make several changes," said Australia's chairman of selectors Trevor Hohns.

"We will have a better idea as to how we are placed once Stuart MacGill and Darren Lehmann have undergone fitness tests.

"Brad Hogg is a ready-made spinner who can come in for Stuart MacGill if he isn't fit, or we can take up the option of playing two spinners."

The Sydney Cricket Ground usually favours slow bowlers, giving left-arm wrist spinner Hogg, 32, an opportunity to play his fourth Test

Williams, 28, is a bowler of raw pace who has played seven one-day internationals.

Bracken, 26, is a tall left-armer from New South Wales with 11 one-day caps.

Selectors chose Katich over Martin Love, who made 100 not out in the second Test against Bangladesh in Cairns in July.

He was dropped for the Perth Test against Zimbabwe when Damien Martyn regained fitness after breaking a finger during the World Cup early in the year.

Katich, 28, is a stylish left-handed batsman and left-arm wrist spinner who played his only Test during the 2001 Ashes tour.

"Martin Love was certainly considered, but on this occasion we felt Simon's bowling record on the Sydney Cricket Ground would prove valuable," said Hohns.

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