England's seamers have scythed through Australia's last six wickets to skittle the hosts for a first-innings total of 98, a record test low against the English at the Melbourne Cricket Ground.
With the series level at 1-1, victory at Melbourne would give the tourists their first Ashes triumph on Australian soil since Michael Gatting's team won the series in 1986/87.
The hosts' previous lowest total was 104 in the inaugural match of England's first test tour of Australia in 1876-77. The hosts won that test by 45 runs.
Australia's capitulation in 42.5 overs saw tea called early after rain at lunch had delayed the start of the second session by 45 minutes.
England paceman James Anderson struck twice shortly after lunch, removing Steve Smith (six) in his third over with an outswinger that nicked the bat on the way to wicketkeeper Matt Prior on an overcast day at the MCG.
The seamer then had Michael Clarke caught behind by Prior for 20 with a similar delivery that swung late four overs later, stunning the more than 70,000 people packed into the ground.
Wicketkeeper Brad Haddin survived only seven more balls before flashing at Tim Bresnan, his flat-footed drive flying straight to England captain Andrew Strauss at first slip.
With England's "Barmy Army" of supporters raucously singing "God Save the Queen", Anderson picked up his fourth wicket three balls after Haddin's dismissal, having Mitchell Johnson caught behind by Prior for a duck.
Mitchell's dismissal saw the hosts slump to 77 for eight, having lost three wickets without adding a run.
Peter Siddle managed 11 runs before edging Tremlett to Prior and the towering seamer then completed the rout soon after by having Ben Hilfenhaus caught behind for a duck, handing Prior his sixth catch for the day.
Australia paceman Ryan Harris was 10 not out.
Anderson finished with 4-44 from 16 overs having taken the key wicket of in-form Mike Hussey, while Tremlett finished with 4-26. Bresnan finished with 2-25 after dismissing opening batsman Phillip Hughes for 16 in the morning session.
Scoreboard on the opening day of the fourth Ashes Test between Australia and England at the Melbourne Cricket Ground
Australia 1st innings
S. Watson c Pietersen b Tremlett 5
P. Hughes c Pietersen b Bresnan 16
R. Ponting c Swann b Tremlett 10
M. Clarke c Prior b Anderson 20
M. Hussey c Prior b Anderson 8
S. Smith c Prior b Anderson 6
B. Haddin c Strauss b Bresnan 5
M. Johnson c Prior b Anderson 0
R. Harris not out 10
P. Siddle c Prior b Tremlett 11
B. Hilfenhaus c Prior b Tremlett 0
Extras (lb2, nb5) 7
Total (all out, 42.5 overs) 98
Fall of wickets 1-15 (Watson), 2-37 (Hughes), 3-37 (Ponting), 4-58 (Hussey), 5-66 (Smith), 6-77 (Clarke), 7-77 (Haddin), 8-77 (Johnson), 9-92 (Siddle), 10-98 (Hilfenhaus)
Bowling Anderson 16-4-44-4, Tremlett 11.5-5-26-4 (1nb), Bresnan 13-6-25-2, Swann 2-1-1-0.
Umpires Aleem Dar (PAK), Tony Hill (NZL)
TV umpire Marais Erasmus (RSA)
Match referee Ranjan Madugalle (SRI)