England are on course for another convincing Ashes defeat after they were outclassed on a lively Perth surface and suffered another addition to their ever-lengthening casualty list.

Knowing they needed a vastly-improved performance in the third Test if they were not to lose both the series and the Ashes, the tourists instead reserved their worst effort of the tour for the crucial opening day.

Dismissed for a lowly 185 after winning the toss again and deciding to bat, they were then smashed all around the WACA, with Ricky Ponting guiding Australia to within 59 of parity on 126 for two with a whirlwind 43.

Perhaps the most worrying news for their long-term prospects of beating any Australian opposition before the end of the tour was the revelation that Yorkshire fast bowler Chris Silverwood had been sent for a scan after going over on his left ankle.

Having already sent two fast bowlers home from the tour with knee injuries - Darren Gough and Simon Jones - the prospect of injury to one of their replacement players crowned yet another frustrating day for the tourists after indisciplined batting once again handed the advantage to their powerful opponents.

Just like the opening two Tests in Brisbane and Adelaide, the tourists were given a solid start before a record first day WACA crowd of 22,523 were treated to the all-too- familiar scenario of a collapse, this time losing seven wickets for 84 in in 34 overs, with Brett Lee celebrating his return to international cricket with a fiery and hostile performance which earned him figures of three for 78.

As if that was not enough of a humiliation, Australia even had time to poke fun at the tourists by introducing part-time seamer Damien Martyn to the attack for the final over before tea and he promptly dismissed top scorer Robert Key just three short of a battling half-century.

''Steve Waugh likes to play a few mind-games and I don't think the batsman was expecting a guy like Damien Martyn to actually come on,'' revealed Lee, who reached speeds of 95mph at one stage.

''He might have relaxed for that split second and that cost him his wicket - it was a great piece of captaincy by Steve to do that.''

Key, virtually the only member of the top order to demonstrate the determination and application to succeed on a wicket rated as Perth's fastest for 20 years, agreed, adding: ''That would be absolutely bang on.

''When someone is bowling 95mph at you and then someone comes on bowling 60mph you think it's happy days - I'll smash a few out of the park - and it's probably where I slipped up.

''Steve Waugh's been pretty clever there, but I was absolutely gutted. Marcus Trescothick came up to me in the dressing room and said 'Gillespie, McGrath, Lee, Warne and you get out to Martyn!'''

Lee, dropped at the start of this series after a disappointing return against Pakistan in Sharjah, provided the focal point for as menacing a spell as has been seen at this ground since Dennis Lillee and Jeff Thomson were in their pomp in the mid-1970s.

Mixing bouncers with full length deliveries, Lee dominated the England batting line-up and tore through the top and middle order, removing Trescothick to a catch behind from his tenth delivery of the day.

That demise prompted a collapse, aided by a mix-up between Michael Vaughan and Mark Butcher which led to the Surrey left-hander needlessly being run out, before Lee intervened again to remove captain Nasser Hussain to a catch behind, while Craig White edged lamely to slip.

But his most menacing spell was directed at Key and Alex Tudor, who bore the brunt of two overs of raw pace and was hit twice on the upper body before edging Shane Warne to slip for his only wicket of the innings.

''When you go out there you have a choice to make whether or not you're going to play the waiting game and look to leave McGrath, which is what I tried to do today, or whether you're going to go after him,'' added Key.

''If you take the initiative then hopefully he'll bowl a few more bad balls. Sometimes you'd rather go out showing positive intent than hanging around and nicking one behind, but unfortunately today that didn't really come off.''

Humbled by their shambolic efforts with the bat, the tourists were almost equally ineffective with the ball, Silverwood's four overs with the new ball costing 29, while Tudor was almost as expensive after conceding 51 from eight overs.

Even before the start they lost the experience of Andrew Caddick after he failed to shake off the back spasm which affected him during the second Test defeat in Adelaide, and England also dropped Matthew Hoggard after two ineffectual performances during the series, leaving them with an attack boasting just 48 Test appearances between them.

That lack of experience soon became apparent with Australia racing to an opening partnership of 31 in only six overs until they received an unexpected bonus when Justin Langer was defeated by Silverwood's throw from deep attempting an ambitious third run.

Matthew Hayden followed seven overs later when he hooked Steve Harmison to Tudor in the deep, but his partnership with Ponting was worth 54 by the time he fell as Australia raced along at six runs an over.

To complete England's miserable day, Trescothick dropped Martyn shortly before the close off White at slip - a mistake which prompted captain Hussain to fall to his knees with his head bowed to sum up his feelings at his side's shortcomings.

l Silverwood was due to undergo a scan on his left ankle last night.

Should the Yorkshire bowler be ruled out of the remainder of this Test, England would be left with only three seam bowlers - Tudor, Durham's Harmison and all-rounder White - on a wicket expected to get even quicker today.

Off-spinner Richard Dawson should be able to provide some relief.

But England have already ruled out the possibility of Michael Vaughan contributing his occasional off-spin because of his tender right knee