Intrigue has deepened into Marnus Labuschagne’s hold on an Australian Test spot with the under-fire No.3 not in his usual batting rotation in the main nets training session at Newlands on Sunday.

In a highly-unusual development, the Queenslander padded up far later than he normally does during the session ahead of the series-deciding finale against South Africa in Cape Town beginning Tuesday.

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Net sessions normally revolve around the energetic Queenslander, who likes to face the quicks and bat at length, usually alongside his mate Steve Smith.

But on Sunday Labuschagne sent down a few deliveries of leg-spin to Cameron Green in the middle before engaging in a lengthy chat with coach Andrew McDonald and Smith, who had spent about 25 minutes receiving throwdowns from Michael Di Venuto in the nets.

As the chat continued, the documentary crew filming the latest edition of The Test closed in on the chat and were recording the extended chat.

Marnus Labuschagne didn't bat for a long period of Australia's session on Sunday. Photo via @BenCameron23Marnus Labuschagne didn’t bat for a long period of Australia’s session on Sunday. Photo via @BenCameron23Source: Supplied

Labuschagne grabbed one of Smith’s bats to shadow bat for a period and about 20 minutes into the chat, the champion Australian batter wrapped an arm around the neck and chest of his mate in an embrace.

An astute net watcher said the body language of Labuschagne on Sunday was similar to that which unfolded when he was dropped from the Australian team in Barbados during the tour of the Caribbean last year.

At that stage, there was already confirmation he had been dropped. There has been no public disclosure leading into the decider between the world’s two top ranked teams.

After the chat with the Australian coach, Labuschagne dropped his strides and began padding up at 10.55am.

With Beau Webster having a chat to him, Labuschagne looked as flat as a tack while sitting on an esky drinking a bottle of water before entering the net after 11am, where he batted for almost an hour alternating with Cooper Connolly.

Nor was he overly convincing in the period he spent in the nets, edging at least three deliveries from Josh Hazlewood, Scott Boland and Beau Webster during the stint before walking back to the locker rooms with Josh Hazlewood.

On Saturday Cameron Green faced the new ball against Michael Neser when about the handful of Australians to use the optional training session.

Matt Renshaw, Alex Carey and Nathan Lyon were the others involved in that session.

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Prior to training, Carey spoke to the travelling press pack and noted the frustration that had placed Labuschagne’s career at risk, notably his propensity to get out after getting a start. He has not scored a Test century in his last 47 innings.

One the world’s top-ranked Test batsman, he has made six scores between 30 and 49 in his last nine innings without going on to nail the big score that would have eased frustration and speculation about his spot in the Australian team.

“I guess we all know Marn and (have) spoken a bit about him in the past, and you know his 30s have been frustrating for him in the way that he’s been playing so well to that point,” Carey said.

“That is the game of cricket. You can’t give an inch any time, and he’s really hungry, and understanding that his role is to go on and convert those runs.

“So, again, (he has to) keep doing what he’s doing, but do it for longer. That is what he’s thinking as well.”

It is a rarity under the current set up for the Australian Test team for there to be so many moving pieces, particularly given the series is still alive.

While Green looks a certainty to return in place of Nic Maddinson, who did spend time in the nets on Sunday, Josh Inglis shapes as a prospect to come into the team in place of Labuschagne.

Victorian Sam Harper, who enjoyed a stellar Sheffield Shield season at the top of the order, also spent a significant amount of time practicing his fielding with the wicketkeeper gloves on.

Smith, meanwhile, had a lengthy chat with Di Venuto after his session in the nets, the angle of the bat face.

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After his lengthy discussing with McDonald and Labuschagne, with captain Pat Cummins joint the group for a period, before walking laps of the ground while mucking around with a Sherrin, opting against a session in the middle.

Smith, who is returning to the scene of the Sandpapergate scandal eight years ago, was struck on the head and assessed for concussion in Durban and then had a neck issue in Gqeberha which hindered him when at the crease in his first innings.

Similarly to Labuschagne, who fell to a brain fade when trying to loft Simon Harmer out of the ground while hitting into a strong gale, Smith played a poor shot to fall to Kagiso Rabada.

But Carey said the Australian superstar is fine and looking forward to the challenge in Cape Town.

“Steve, he’s going well. (I have) spent a lot of time with him, as I always do, and he’ll start prepping for Tuesday today,” he said.

“He’ll have a hit. I think he’s 100 per cent fine. So (I’m) looking forward to seeing Steve get out there and play and hopefully score the big runs we’ve seen him do.

“He’s had a couple of starts. He was impacted a little bit with his neck, but he’s ready to go.”