Australia coach Justin Langer remains confident David Warner can end his form slump with the bat in the final Ashes Test at The Oval, beginning on Thursday.

Key points: David Warner has scored only 79 runs during the Ashes series

David Warner has scored only 79 runs during the Ashes series Warner's paltry return contrasts with Steve Smith's tally of 671 runs at an average of 134.20

Warner's paltry return contrasts with Steve Smith's tally of 671 runs at an average of 134.20 Australia coach Justin Langer has called on the entire battling line-up to improve in the final Test

Warner, playing his first Test series since returning from his suspension following the ball-tampering controversy in South Africa, has endured a run of outs in the Ashes, which Australia retained courtesy of its win at Old Trafford.

The former Australia vice-captain has been dismissed six times by England veteran Stuart Broad this series, including three ducks in his past three knocks, while tallying 79 runs at the embarrassing average of 9.87.

But Langer backed Warner to return to his best form, as Australia looked to complete its first series win in England since 2001.

"Davey hasn't had a great series but imagine how good the team will be when he starts having a great series," Langer said.

"We're hopeful he'll do that in the next Test."

Warner's poor form is in stark contrast to the performances of Steve Smith, who also made his return to the Test arena at the beginning of the Ashes series following his ball-tampering ban.

Smith has scored a staggering 671 runs from five innings at an average of 134.20, having posted three centuries and two half-centuries.

Steve Smith has played the starring role with the bat for Australia. ( AP: Rui Vieira )

His lowest score in the series is 82, while he could have added to his mammoth tally of runs had he not been ruled out of the third Test in Headingley because of concussion.

Langer said Warner's contributions to the Australia Test XI during his career must not be forgotten when critics point out how he has fared in England compared to Smith.

"Steve Smith has done a lot for Australian cricket for the last few years actually, and so has Dave Warner," he said.

'You've still got to perform'

Langer is more concerned with fixing the woes of other members of Australia's batting line-up, with its unsettled top six recording largely modest returns.

Marnus Labuschagne, having gone from strength to strength since filling in as Smith's concussion substitute, is a notable exception.

Labuschagne has emerged as the nation's next first drop with four half-centuries on the trot.

Matthew Wade posted a series-opening century and formed a key second-innings stand with Smith at Old Trafford.

Cameron Bancroft and Marcus Harris have each been given two Tests as Warner's opening partner but failed to reach 20.

Usman Khawaja was dropped after three Tests, while Travis Head has logged scores of zero, 25, 19 and 12 since salvaging a draw at Lord's.

Marnus Labuschagne has held his head up high in his debut Ashes series. ( AP: Jon Super )

"Travis Head is new to Test cricket, Marnus is new to Test cricket, Marcus Harris is new to Test cricket, Cameron Bancroft is new to Test cricket," Langer said.

"You can't just give them that experience, they've got to earn that.

"You've still got to perform, whether you're young or a veteran, but we also have to recognise they are young batsmen and it's a really tough school.

"Hopefully they'll come through … we're very thankful to have Steve. I've never seen batting like that."

AAP/ABC