England was three wickets away from regaining the Ashes and completing Australia's humiliation at Trent Bridge after reducing the tourists to 241-7 by stumps on the second day of the fourth test on Friday.
The Australians will resume needing 90 more runs just to make England bat again, having started their second innings 331 runs behind following England's positive declaration at 391-9.
Ben Stokes was the inspiration as England claimed four wickets late in the afternoon session to end Australia's fleeting fightback.
Stokes dismissed Chris Rogers for 52, David Warner for 64 and Shaun Marsh for two before taking a brilliant catch off Stuart Broad's bowling to send back Steven Smith for five.
Australia stumbled to tea on 138 for four, still 193 runs behind, with Michael Clarke on nought and Adam Voges on two facing a desperate fight to stop England winning the game and reclaiming the Ashes.
Rogers and Warner had shared an opening partnership of 113 to give the touring side a foothold in the match after being bowled out for 60 on the opening day.
Mitchell Starc led the Australian revival in the morning when they took five England wickets for 119 runs before the hosts declared shortly before lunch on 391 for nine.
England, 2-1 up in the series, had resumed on 274 for four.
Root, on 130, drove loosely at a wide delivery from Starc and nicked a catch to wicketkeeper Peter Nevill.
Nightwatchman Mark Wood made a breezy 28 off 32 balls, including five fours, before he was bowled by a full delivery from Starc.
The tall left-armer produced another cracking ball to bowl Jos Buttler for 12 and Stokes, on five, tickled Josh Hazlewood tamely down the leg-side to Nevill.
Moeen Ali and Broad stopped the rot with an entertaining ninth-wicket partnership of 58.
Mitchell Johnson returned to the attack to dismiss Moeen for 38, Smith diving to take a superb one-handed catch at second slip.
Broad's eight dismantles Australia on opening day
Broad was unbeaten on 24 when captain Alastair Cook declared shortly before lunch, giving the Australian openers three overs to survive.
They managed that and set about reducing England's lead in the afternoon.
Warner, on 10, was badly dropped by Cook at first slip off Broad and, on 42, Ian Bell spilled a harder chance off Stokes.
Rogers, caught by Root off Wood on 47, was reprieved when television replays showed the bowler had over-stepped the crease but five runs later he was on his way back to the pavilion, brilliantly taken by Root.
Warner skied Stokes to Broad at wide mid-on, Marsh edged the right-armer to Root at third slip and Smith flayed Broad to cover point where Stokes held a fine low catch.
Australia 2nd Innings
Chris Rogers c Root b Stokes 52
David Warner c Broad b Stokes 64
Steve Smith c Stokes b Broad 5
Shaun Marsh c Root b Stokes 2
Michael Clarke c Bell b Wood 13
Adam Voges not out 48
Peter Nevill lbw b Stokes 17
Mitchell Johnson c Cook b Stokes 5
Mitchell Starc not out 0
Extras: (16b, 15lb, 1w, 3nb) 35
TOTAL: (for 7 wickets) 241
Source: Reuters And AP