Australia 295 (Smith 71, Woakes 3-61) and 135 for 0 (Khawaja 69*, Warner 58*) need another 249 runs to beat England 283 (Brook 85, Starc 4-82) and 395 (Root 91, Bairstow 78, Crawley 73, Starc 4-100, Murphy 4-110)
London: England were frustrated by Australia's strong start to a chase of 384 before rain wiped out half of the fourth day of the final Ashes Test at The Oval.
Looking to pull off their second-highest run chase in Test cricket and the best on this ground, Australia made untroubled progress to 135-0.
Usman Khawaja is unbeaten on 69 and David Warner 58 not out, with the tourists needing another 249 runs to win.
After announcing his retirement at the close on day three, Stuart Broad was given a guard of honour by the Australia players when he emerged to resume his innings on Sunday morning.
He pulled Mitchell Starc for six from what turned out to be the final delivery he will face in Test cricket, before last man James Anderson was lbw to give a fourth wicket to Todd Murphy and leave England 395 all out.
Broad bowled the first over of Australia's innings to his old nemesis Warner, but England were off-colour with the new ball, not helped by a slow, lifeless pitch.
The rain arrived at around 14:40 BST, with a possible 48 overs still remaining in the day. The forecast is better for Monday, albeit with a chance of showers. There are 98 overs scheduled for what could be a grandstand finish to a superb series.
Australia have already retained the Ashes and avoiding defeat would give them a first series victory in this country since 2001. England are looking for the win that would level the score at 2-2.