Joe Root was dropped twice before lunch on the first day of the final Ashes Test as Australia's decision to send England in allowed the hosts to reach 86 for one at the Oval.

Chasing a first series win on these shores since 2001, Tim Paine won the toss for the fourth time this summer and made the surprising call to give England's batsmen first use of a pitch renowned as one of the truest on the circuit.

Pat Cummins made one breakthrough with the new ball, seeing off Joe Denly for 14, but Rory Burns made a sound 42 not out and Root was put down by Peter Siddle and Paine on his way to a fortunate 28no.

Opening the batting has been a fiendishly difficult endeavour this summer and Cummins had the new Dukes ball skipping past Burns' outside edge twice in the first over.

The Surrey captain was given out lbw for four as Josh Hazlewood kept the pressure up from the other end but Burns immediately referred the decision and was reprieved on height.

Things were no easier for Denly, who twice felt bat on ball after attempting to leave and picked up a couple of lucky boundaries while not in full control.

Cummins struck in the ninth over, tempting Denly outside off stump and picking up an obliging outside edge that Steve Smith juggled at second slip before hanging on.

Remarkably, by putting on just 27 the England pair had made the biggest first-wicket partnership of the series. Whether that is enough to extend Denly's international career remains to be seen, but in averaging just under 25 he has hardly made a watertight case.

Siddle offered Root a soft start to his innings, with the 34-year-old shipping 18 runs in three overs of very gentle seam bowling.

With Burns looking increasingly settled at a ground he knows so well, the wisdom of Paine's decision was starting to seem dubious.

Australia had the chance to reset the tone when Root, on 24, top-edged a pull off the ever-impressive Cummins, leaving Siddle a simple take at fine leg. Somehow the veteran allowed the ball to slip through his grasp.

If dropping the opposition's best batsman once is a mistake, doing so twice is a sin.

And so it was when Root, having added just a single to his score, sent a edge in the direction of first slip.

Paine decided to leap in front of David Warner and take it one-handed but the ball bounced out of his glove. There were no further chances before the break, with Burns the steadying influence.