Australia remains alive in the gripping Ashes Test, needing another 209 runs for victory against England.
Chasing a record fourth-innings total of 522, Brad Haddin and Michael Clarke displayed an unbeaten sixth-wicket stand of 185 to steer Australia to 5 for 313 at stumps.
Their sometimes nerve-racking partnership gave Australia hope of batting out the Test after an England victory had appeared inevitable earlier on day four.
Marcus North's dismissal in the middle session was England's third strike after lunch and left Australia 394 runs short of its target with only five wickets in hand.
However, Clarke (125no) stood up to the plate for Australia and in Haddin, who added 80 to the pair's unbroken stand of 185, found a capable partner.
Victory is still a difficult prospect on day five as Australia looks to break a bevy of Test cricket records to take a 1-0 lead in the Ashes series.
According to the ABC, the highest successful fourth-innings total in Test history came in 2003 when the West Indies scored 7 for 418 to defeat Australia at St John's.
Australia's best ever Test run chase was 61 years ago - scoring 3 for 404 to defeat England at Leeds in the second Ashes Test of the 1948 series, the ABC said.
No side has ever come close to that at Lord's, where Australia's 3 for 329 was enough for victory against England in the 1975 Ashes series.
