By Ian Ransom
PERTH (Reuters) - An epic and unbeaten 301-run stand by Australia captain Steve Smith and Mitchell Marsh left England's hopes of retaining the Ashes in jeopardy on day three of the third test at the WACA on Saturday.
On an agonising day for Joe Root's team, Smith broke English hearts with his second double-century after recalled all-rounder Marsh celebrated his maiden ton.
The pair pushed Australia to 549 for four and a first innings lead of 146 runs, rendering England's 403 a hopelessly inadequate total on a featherbed wicket.
They strode off to a standing ovation, with Smith unbeaten on 229 and Marsh 181 not out, pushing towards a double-century of his own.
"It felt really good yesterday, I was in the zone. I wanted to cash in today," Smith said before he exited the ground to roaring applause.
"We wanted to be out in the middle and just keep batting."
Two-nil down after losses in Brisbane and Adelaide, England's hopes of keeping the series alive to Melbourne appear bleak.
On day two, Dawid Malan and Jonny Bairstow had English chests bursting with pride after compiling 237 runs for a record fifth-wicket partnership at the WACA.
But the mark lasted less than a day, as Smith and Marsh smashed 57 boundaries between them to leave England praying for the mercy of rain.
Showers are forecast for days four and five, but the weather may not be enough to save the tourists, who managed only a single wicket despite no fewer than seven players rolling over their arm throughout the day.
Having torched England for 107 runs in the middle session, Smith and Marsh plundered another 128 after tea, as the tourists' lack of pace was ruthlessly exposed.
"It's been a very, very tough day for our team," England assistant coach Paul Farbrace told reporters.
"What can we do? We've got what we've got... When it comes to flatter pitches, we don't have that express pace."
Smith punished England with 215 at Lord's in 2015 but set himself a new personal best at the WACA in a masterclass of patience, precision and timing.
His unbeaten 390-ball knock has him fourth on the list of highest innings at the WACA, with the possibility of further promotion on day four.
He reached the three-figure mark, his seventh against England, when he whipped paceman James Anderson through the leg side for four.
The second hundred came with a single off all-rounder Moeen Ali, and he bounded down the wicket roaring in triumph to the delight of a big day three crowd.
He also notched his 1,000th run for the year, and joined former Australia opener Matthew Hayden in reaching the mark four years in succession.
Marsh completed a rare family trio of Ashes tons.
His older brother Shaun Marsh scored an unbeaten 126 in the second test win at Adelaide Oval, and his father Geoff, beaming with pride in the heaving WACA crowd, posted 138 as an opener at Nottingham in the 1989 series.
The younger Marsh cut paceman Stuart Broad to the fence to bring up his ton from 130 balls and pumped his fist in jubilation, having scored only two half-centuries in his previous 21 tests.
While stopping short of declaring England's spirit broken, Marsh said they were "obviously tired".
"Today was just a great day for Australia. To only lose one wicket for the whole day has really put us in a strong position," said the 26-year-old.
Moeen had Shaun Marsh caught at slip for 28 in the first hour but it was to prove England's only highlight.
Farbrace insisted the Ashes were still alive.
"We've got two more days to play. It's going to be tough, of course it's going to be tough," he said.
"We've got to show some guts and determination."
(Editing by Sudipto Ganguly)