England eked out four Australia wickets between breaks for rain and bad light on day one of the fifth Test at the SCG.

Phil Hughes saved the tourists from a rare wicketless session in this winter's Ashes, when he fell in the final over before lunch, and England struck a second time with what turned out to be the final delivery before an interruption - Graeme Swann grabbing the important wicket of debutant number three Usman Khawaja.

The upshot was a home total of 134 for four when rain moved in by mid-evening to raise the probability of an early close.

Three home batsman - Hughes, Khawaja and Shane Watson - all got set but were dismissed between 30 and 50, and it was England who could be happier with their day's work so far.

Watson and Hughes guided the hosts safely to 55 without loss, after stand-in captain Michael Clarke had chosen to bat first, until the left-hander fenced a catch high to third slip Paul Collingwood off the deserving Chris Tremlett.

A second half-century stand followed between Watson and Khawaja. But the opener - who had left expertly throughout - then followed one from Tim Bresnan that he need not have, and edged to Andrew Strauss at first slip.

Australia must win here to square the series at 2-2 and therefore prevent Strauss' team becoming the first tourists since 1986/87 to win the Ashes outright down under.

Strauss was unconcerned after losing the toss, reasoning heavy overnight rain and cloud cover presented the possibility of sideways movement.

There was too, for Tremlett in particular, with the new ball.

But after their debilitating 98 all out in the first innings of the fourth Test at Melbourne, Australia seemed programmed this time to eliminate risk.

So it was that Watson went without a boundary until early afternoon, when he clipped James Anderson off his pads from the 89th ball he faced.

Hughes was slightly more adventurous, but never reckless until his fateful mistake.

It was a measure of England's failure with Plan A - not for lack of effort or accuracy - that Swann's off-spin entered the attack only 20 overs into the match.

Anderson had been warned by Billy Bowden for running on the pitch in his first spell, and switched first to the Paddington end and then round the wicket too.

But nothing England tried would bring the breakthrough, until Tremlett struck.

Pakistan-born Khawaja, the first Muslim to play for Australia, appeared nerveless as he made an assured start to his Test career - tucking his first ball for two off his pads and then crunching a pull for four off the next as Tremlett completed the over interrupted by Hughes' dismissal.

Watson clipped Bresnan for a legside four to bring up the 50 stand, soon after play resumed under lights, but he was gone two balls later.

A noisy, and mixed, reception greeted Clarke's walk to the crease. He responded with a push through cover for three off Bresnan first ball but could add only one more either side of a first rain break before guiding a routine catch to gully off the same bowler.

It was perhaps a bigger blow to home hopes, however, when Swann saw off Khawaja in the first over of his second spell - the left-hander mistiming a sweep which looped to backward square-leg.

Within seconds, Khawaja was being followed off the pitch by the remaining players as rain began to fall.