(CNN) -- Michael Clarke and Brad Haddin defied England with an unbroken sixth wicket partnership of 185 to set up the unlikely prospect of an Australia victory on the final day of the second Ashes Test at Lord's
Haddin (left) and Clarke walk off at the end of the fourth day at Lord's.
Australia were 313 for five wickets at the close of the fourth day, still needing 209 runs to go one up in the best of five Test series.
The pair came together with Australia reeling on 128 for five wickets and set to suffer their first defeat at the home of cricket since 1934.
But vice-captain Clarke, who was unbeaten on 125, and wicketkeeper Haddin (80 not out) combined for a record sixth wicket partnership at Lord's for Australia.
England will rest their hopes on the second new ball early on the fifth morning as they bid to refresh their victory charge.
Home captain Andrew Strauss declared their second innings on 311 for six at the start of the fourth day.
With Andrew Flintofff, playing his final Test at the home of cricket, producing a superb opening spell, Australia were soon in trouble.
Flintoff had Simon Katich (6) neatly caught in the gully by Kevin Pietersen for six and then removed fellow opener Phillip Hughes for 17.
Hughes edged to Strauss at slip and immediately walked off as it appeared the catch was cleanly taken.
Captain Ricky Ponting signaled for him to stay, but Rudi Koertzen, after consulting with fellow umpire Billy Doctrove, gave him out without calling for evidence from the TV official.
Ponting, who had batted grittily before lunch, added just one more after the break when he tried to cut Stuart Broad and the ball found his stumps.
He had made 38 to leave Australia 78 for three and in deep trouble.
That became 120-4 when Mike Hussey was adjudged to have edged off-spinner Graeme Swann to Paul Collingwood at slip after making 27.
TV replays indicated Hussey had not touched the ball, to add to the Australian sense of injustice with defeat staring them in the face.
Flintoff returned for a second spell to hit Clarke on the helmet, but it was Swann who claimed the fifth wicket as he bowled Marcus North for six.
Victory seemed within the home side's grasp but it proved the final wicket to fall on a topsy-turvy day.
England battled to a draw in the first Test at Cardiff after a match dominated by Australia.