A Nathan Lyon-inspired Australia were on the verge of a big victory in the first Ashes Test as they bowled England out for 297 at lunch on day four at the Gabba on Saturday.
The hosts need just 20 to win in Brisbane after another English batting collapse, with spinner Lyon passing 400 Test wickets for Australia.
After starting the morning in a reasonable position following a superb fight back from Joe Root and Dawid Malan on Friday, the English lost eight for 77 in the extended first session.
England's batting issues at the Gabba were mirrored in the broadcast compound, where a power failure resulted in the worldwide television feed going down for 45 minutes.
No wickets fell during this period but when the broadcast problems were finally resolved, Lyon struck.
The 34-year-old off-spinner had looked ineffectual on Friday as he searched for his milestone 400th wicket.
But he finally broke through when Malan got an inside edge onto his pad and the ball popped up to Marnus Labuschagne at silly mid-off, sparking huge celebrations around the Gabba. Malan made 82.
Lyon, in his 101st Test, became just the 16th player worldwide to achieve the feat of 400 Test wickets, and only the third Australian after Shane Warne and Glenn McGrath.
England were rocked in the next over when Root, on 89, wafted at a ball outside off stump from Cameron Green and got a thin edge to Australian wicketkeeper Alex Carey, leaving England 229-4 and Root still searching for his first Test century in Australia.
Lyon then struck again, getting a ball to bite and leap off the Gabba pitch and take the thick edge of Ollie Pope's bat, Steve Smith taking a comfortable catch at slip.
Ben Stokes and Jos Buttler tried to steady the ship as Australia took the new ball and reduced the deficit to 12 runs, but new Australian captain Pat Cummins brought himself on and had immediate success.
Bowling with real pace and aggression, Cummins squared Stokes up with a brute of a ball that took the outside edge and flew to Green in the gully, leaving England 266-6.
Two runs later, Josh Hazlewood, who was under an injury cloud after not bowling after tea on Friday, drew a faint edge from Buttler to leave England staggering.
Ollie Robinson joined Chris Woakes at the crease and the pair put on 18 runs to ensure Australia had to bat again.
But Robinson attempted a reverse sweep off Lyon and spooned a simple catch to Travis Head at backward square leg.
Lyon took his fourth wicket just before the scheduled lunch break when he bowled Mark Wood, who had attempted an extravagant drive.
With nine wickets down, the umpires called for an extra 30 minutes to be played before lunch and Green wasted no time, snaring Woakes, who tried to steer the ball over the slips but only succeeded in getting a thin edge to Carey.