AFP - Australia were left needing to set a new world record if they were to win the second Test against England here at Lord's.
England, when rain forced an early close on Saturday's third day, were 311 for six, a lead of 521, with two days remaining.
Whether they declared on that total overnight, as seemed likely, or batted on, it meant Australia would have to set a new world record for the highest fourth innings total to win a Test, surpassing the 418 for seven made by the West Indies against Australia in Antigua in 2002/03.
Both totals were well in excess of the corresponding record for a Test at Lord's, the 344 for one made by the West Indies against England in 1984.
England, bidding for a first Test win over Australia at Lord's in 75 years, were indebted to a stand of 86 in 74 balls between Paul Collingwood (54) and wicket-keeper Matt Prior (60).
Their innings had stalled during the second session but Prior, who faced just 42 balls with nine fours, regained the initiative, and helped justify captain Andrew Strauss's decision not to enforce the follow-on, before he was run out by Marcus North's direct hit.
Collingwood, who'd batted for over six hours to help England secure a draw in last week's series opener in Cardiff, posted his third fifty in four innings in a brisk 72 balls. They were contrasting innings but each ideally suited to England's task at hand.
He was eventually out for 54, having shared a stand of 51 in 50 balls with Andrew Flintoff, who ended the day on 30 not out.
Flintoff took England's lead past 500 with an off-driven four off struggling left-arm quick Mitchell Johnson, who at one stage completely lost all semblance of line and length.
Much of Australia's fielding was unusually shoddy, with several fumbles, a dropped catch by captain Ricky Ponting no less and a scruffy display by wicket-keeper Brad Haddin, who conceded 16 byes, aiding England's cause.
Neither Ravi Bopara nor Kevin Pietersen were at their best during a third-wicket stand of 73.
Bopara's scratchy innings of 27 finally came to an end when he turned off-spinner Nathan Hauritz straight to Simon Katich at short leg.
Pietersen, who had been regaining some of his old fluency, fell for 44 when caught off the inside by Haddin off persevering paceman Peter Siddle.
Bopara had made just nine when he edged Siddle only for Ponting, at second slip, to stun his side by dropping the seemingly routine chance.
At lunch, England were 57 without loss after Strauss, who made 161 in the first innings, had opted not to enforce the follow-on
But off-spinner Hauritz, whose selection for this tour was much derided in Australia, brought his side back into the match with two wickets for no runs in eight balls as both Strauss and fellow opener fell for 32.
Cook was lbw before Strauss edged a well-flighted, turning, delivery to Michael Clarke at first slip.
Johnson had bowled poorly during England's first innings and his problems showed no sign of easing when his second delivery after lunch barely landed on the cut strip, forcing Haddin to dive in front of first slip to take the ball.
Earlier, Graham Onions finised off the work started Friday by James Anderson with two wickets as Australia, 156 for eight overnight, were bowled out for 215, 11 runs shy of the follow-on avoidance target of 226, after England had made 425.