STEVE SMITH DOUBLE TON AND MITCHELL MARSH CENTURY SEE AUSTRALIA DOMINATE IN PERTH

AUSTRALIA CLOSE ON 549-4, A LEAD OF 146, AT THE WACA

Steve Smith hit his second Test double hundred and shared an unbeaten fifth-wicket stand of 301 with Mitchell Marsh as Australia assumed complete control of the third Ashes Test.

While Smith (229no) continued his imperious form with his highest Test score, Marsh (181no) marked his return to the Australia side by scoring his maiden Test century on his home ground, as the hosts advanced to 549-4 at stumps, a lead of 146.

The England bowlers worked hard but with no lateral movement to assist them, they offered little threat as the Aussies accumulated runs with ever-increasing ease on day three.

At the start of the day, England would still have held hopes of earning a first-innings lead with Australia still some 200 behind the 403 they posted on day two.

Smith, resuming on 92, soon hit the eight runs he needed to go through to his 22nd Test ton and his partnership with Shaun Marsh (28) had stretched to 69 when, seemingly from nowhere, Moeen Ali got one to turn and take the left-hander's edge.

Joe Root took the catch at slip and, even on a lifeless surface, as Mitchell Marsh came out to replace his brother, England could not have imagined that they would fail to take another wicket in the day.

Marsh looked nervy early on, inadvertently chipping the ball just wide of mid-on off Craig Overton - who was bowling despite suffering a hairline crack to a rib on day two - but got himself going with a couple of crisp drives.

The second new ball stopped swinging within a couple of overs, leaving England to bowl with a ball that's only advantage was saving the fielders from chasing it as it raced quickly to the fence.

Smith was in cruise control for much of the day but did show a few signs of tiredness as the tea interval approached, James Anderson finding his outside edge twice and Stuart Broad once, only to see the ball drop short of slip on each occasion.

Anderson thought he had finally removed Smith when he squared up the Australian captain and struck him on the front pad. England reviewed the not out decision but it did not even get as far as ball-tracking once it was shown that Anderson had narrowly overstepped for the only time in the day.

The only consolation for England was that even though the ball was shown to be hitting leg stump it would have stayed with the umpire's call.

If Smith was struggling, if only relative to his usual standards, Marsh was thriving and, having gone past fifty, accelerated towards three figures towards the end of the afternoon session.

A pair of boundaries off Broad in the last over of the session got him there and, with his family watching on, Marsh let out a cry of celebration before a wide smile spread across his face.

The onslaught continued in the evening session and Smith matched Marsh's emotion and then some when he reached 200 - but was a picture of calm by the time he faced his next delivery.

Moeen Ali almost broke a stand that had stretched to 300 by the close when Marsh pressed forward and was a little early through his shot, but the ball again fell just short as Ali dived for a return catch.

Smith offered a similar "chance" off Dawid Malan's part-time leg-spin but otherwise he and Marsh were able to ease their way through to stumps.

The pair will be back on day four looking to add a few more runs before making a declaration, while England could be forgiven for hoping that forecasts of rain in Perth tomorrow prove to be correct with a draw now, realistically, the best result they can hope for.