'We've got the batting in the sheds that can do the job'

Steve Smith has been ruled out of the third Ashes Test in Leeds having failed to recover in time from the concussion he sustained at Lord's.

Coach Justin Langer confirmed the news two days out from the third Test on a cold Tuesday morning at Headingley, with Smith appearing understandably downbeat around his teammates.

As the squad huddle disbanded to begin practice, Smith received a pat on the shoulder from vice-captain Pat Cummins before Langer wrapped his arm around the right-hander as the squad warmed up without him.

Langer and Smith then walked out to the middle to inspect the pitch as the rest of the group limbered up and jogged laps around the outfield.

Smith is consoled by Langer and the support staff // Getty

Team doctor Richard Saw was seen chatting to Smith near the centre square and he had the final say on Smith's involvement in the match, as per Cricket Australia's concussion protocols. Smith requires the approval of Dr Saw before he can resume playing.

"When we followed the protocols he was probably a couple of days off being fit to be selected," said Langer at a press conference.

"It was really a no-brainer. He felt a bit better yesterday but he's not going to have enough time to tick off everything he's got to do.

"It's not unlike England losing James Anderson. He's arguably their best bowler and we're going to lose arguably our best batsman for this Test match.

"It is always a blow. No doubt about that. When you take your best players out it always has an impact.

"We have to make sure our senior players and the younger guys step up and fill what are almost unfillable shoes because he's the best player in the world."

Smith was in a race against time to be fit for the third Test after he was struck by a searing Jofra Archer bouncer on day four of the Lord's Test.

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Smith was the first player in international cricket to be substituted out of a match following the scary blow to the neck from Archer.

While he was keen to bat on following the blow, Dr Saw removed Smith from play as a precaution, and after passing a series of concussion tests resumed his innings.

But after waking up groggy and with a headache on the morning of day five, Smith was subbed out for Queensland's Manus Labuschagne, who starred on Sunday with 59 to ensure Australia drew the second Test and preserved their 1-0 series lead.

Labuschagne appears to be the favourite to take Smith's place in the XI for the clash in Leeds.

Smith now has two weeks to be ready for the fourth Test in Manchester, which starts on September 4, with a three-day tour match in Derby from August 29-31.

Langer tries to cheer up his star batsman // Getty

For Smith to have been cleared to play in Leeds he would have needed to show no symptoms of concussion, gradually return to full activity, pass routine concussion assessments and face fast bowling in the nets to ensure his reaction speeds had not waned.

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Smith has been in imperious form during the Ashes, scoring 142, 144 and 92 in his three innings so far.

His prolific form has seen him rise to No.2 in the ICC Test batting rankings, just nine rating points behind India captain Virat Kohli.

Smith has 378 runs in three innings this series // Getty

While he watched his teammates train, Smith enjoyed a long chat with former Australia captain Mark Taylor, who captained Australia to a win at Headingley in 1997.

Australia require just one more win in the series to retain the Ashes.

2019 Qantas Ashes Tour of England

Australia squad: Tim Paine (c), Cameron Bancroft, Pat Cummins, Marcus Harris, Josh Hazlewood, Travis Head, Usman Khawaja, Marnus Labuschagne, Nathan Lyon, Mitchell Marsh, Michael Neser, James Pattinson, Peter Siddle, Steve Smith, Mitchell Starc, Matthew Wade, David Warner.

England squad: Joe Root (c), Moeen Ali, Jimmy Anderson, Jofra Archer, Jonny Bairstow, Stuart Broad, Rory Burns, Jos Buttler, Sam Curran, Joe Denly, Jason Roy, Ben Stokes (vc), Olly Stone, Chris Woakes.

First Test: Australia beat England by 251 runs at Edgbaston

Second Test: Match drawn at Lord's

Third Test: August 22-26, Headingley

Tour match: Australians v Derbyshire, August 29-31

Fourth Test: September 4-8, Old Trafford

Fifth Test: September 12-16, The Oval