Despite Chris Tremlett's maiden five-wicket Test haul, Australia should level the Ashes series tomorrow morning.

England will begin the fourth day on 81 for five, still needing another 310 to win, after their batting struggles continued against the pace and bounce at the WACA in Perth.

Hussey's second century of the winter helped Australia to 309 all out and into pole position for a series-levelling victory in this fluctuating third Test at the WACA.

Yet to fall for under 50 in five attempts in this campaign, the left-hander finished with 116 on his home ground - leaving England to make 391 in almost seven sessions to retain the urn with two matches still to play.

Tremlett (five for 87) took two of four wickets for the addition of only 32 runs in late afternoon, after Australia had appeared set to bat on for the remainder of the day and set a record-breaking fourth-innings target.

The Sotonian then returned with the second new ball to take his eighth wicket of the match and finish the innings, Hussey caught in the leg-side deep, after James Anderson had become the 13th Englishman to reach 200 Test wickets when Peter Siddle edged to slip.

Australia nonetheless remained strong favourites to prevail, thanks largely to the prolific Hussey's 136-ball 13th Test century - completed with one of his trademark, expertly placed and controlled pulls off Tremlett for his 13th four.

Hussey and Shane Watson (95) completed a century stand for the fourth wicket.

Former Hampshire batsman Watson was the only wicket to fall in the third day's first session, lbw to Tremlett to make it the 14th time he has passed a Test 50 and then failed to convert it to three figures.

He left with a withering look for umpire Marais Erasmus too. But after taking the lbw verdict to DRS, the accepted proof was there that there was no inside edge and Watson was struck in front.

Within minutes, Australia were on the right side of a review when new batsman Steven Smith was given out by Billy Doctrove.

Whether the decision was for lbw or caught at first slip was not clear, but it was soon evident that Smith was staying put in either case.

Hussey had a significant scare on 60 from the last ball before lunch, having to go to DRS to show the ball hitting him too high and therefore overturning Erasmus' decision that he was lbw to Tremlett.

Smith won another marginal lbw rethink from the third umpire, on 28, leaving Anderson still stuck on 199.

But Tremlett's short, leg-side line of attack from round the wicket ended a stand of 75 when Smith fended one behind to Matt Prior.

Tremlett's awkward length confused Brad Haddin, who deflected the ball down on to his stumps; then, either side of Hussey's hundred, Johnson and Ryan Harris came and went for just a single each.

Paul Collingwood replaced an out-of-sorts Graeme Swann and had Johnson poking a catch to cover, and Harris continued his miserable run of scores when he pulled Steven Finn (three for 97) into the hands of deep midwicket.

Andrew Strauss and Alastair Cook had put on 78 in the first innings, only for England to falter alarmingly with the bat.

This time, they managed only 23 before Cook was lbw on the back foot to Harris immediately after the fast bowler had made an early switch to the Lillee Marsh Stand end.

Then Johnson took his seventh wicket of the match, finding Strauss' edge for a routine catch at second slip by Ricky Ponting.

It got worse still for England in the final hour, when Kevin Pietersen followed up his first-innings duck by becoming Ben Hilfenhaus' 50th Test victim when he edged to Watson at first slip for three.

Jonathan Trott (31) soon followed Pietersen back to the pavilion, his edge off Johnson bouncing up off Ponting's fingers and providing wicketkeeper Haddin with a straightforward catch.

That left England on 81 for four and Australia heaped further misery on the tourists before the close by snaring the dogged Collingwood, caught by Smith at third slip for 11 off the bowling of Harris.