Nathan McSweeney had a brutal introduction to Test cricket.

“The South Australian was thrust into Australia’s opening spot — left vacant by modern greats David Warner and Steve Smith — following a “survival of the fittest” bat-off.

Never mind that he had no first-class experience in arguably the only specialist batting position in cricket.

Well, that’s not entirely true. McSweeney was elevated to the top spot in the second Australia A tour game after coming in at four in the first match, behind three actual openers vying for the chance to partner Usman Khawaja in the Test side.

That game started two weeks before the first Test against India.

The 25-year-old had batted as high as three and as low as seven in South Australia’s Sheffield Shield line-up, but never one or two.

Alas, selectors decided he was the man for the job after the highly publicised and somewhat underwhelming contest between McSweeney, 19-year-old New South Wales boy Sam Konstas, Western Australia’s Cameron Bancroft and Victoria’s Marcus Harris.

Bancroft and Harris were always playing from behind in the quest for the Test spot after 10 and 14 games at the top level with averages in the mid-20s.

Konstas seemed the most likely option after scoring two centuries in the first game of the Shield season, a game in which McSweeney scored 55 and 127 not out.

But, whether it was his age, a couple of low scores or McSweeney’s form, Konstas missed out when the Australian squad was named before the first Test of the Border-Gavaskar series.

“Nathan has displayed the attributes we believe will equip him well for Test cricket along with a strong recent record in domestic cricket,” chair of selectors George Bailey said at the time.

“His performances for South Australia and Australia A weighed in his favour and supports our view he is ready for the opportunity at Test level.”

Three games and 40 days later, McSweeney’s first stint as a Test cricketer was abruptly ended as he was dropped for the Boxing Day Test.

And even within his six Test innings, only half were anything akin to normal.

In the opening outing in Perth, McSweeney was summarily blown away by Jasprit Bumrah for 10 and 0.

In Adelaide, he outlasted senior partner Khawaja in a brutal session under lights before falling for 39 on the second morning, then scored an unbeaten 10 of a nominal 19-run victory chase.

In the rain-hit Brisbane game, he fell cheaply to Bumrah again in the first innings before scoring 4 in the Aussies’ frantic and fruitless second innings while chasing rapid runs to set up a victory target that never eventuated.

None of that is to say McSweeney’s return of 72 runs from six innings at an average of 14.4 is great or even good, but what would a pass mark have been for a first-time opener thrust into an unfamiliar position against one of the best bowlers of this generation?

No-one in the Australian top six, aside from Travis Head, has scored more than 17 twice.

Khawaja is averaging 12.6 for the series with a top score of 21, Marnus Labuschagne has an average of 16.4 despite a top score of 64, Steve Smith scored an impressive century at the Gabba but otherwise has scores of 0, 17, 4 and 2.

And it’s part of a trend for the trio that were until recently the tip of the spear for Australia’s batting.

“It has clearly been a challenge at the top of the order for batters throughout the series, and we want to provide the option of a different line-up for the next two matches,” Bailey said as he announced the changes for the MCG.

Mitch Marsh is ostensibly a different conversation because he’s the “all-rounder” in the team, but he bowled just two of 79 overs as Australia’s attack struggled without Josh Hazlewood in the third Test, so his return of 69 runs at 13.8 shouldn’t be discounted either.

If we’re still counting a clearly not fit Marsh as an all-rounder, then it’s worth noting McSweeney took 2-20 in nine overs of off-spin against India A and has career-best Shield figures of 4-89.

“No matter who they picked in that opening position, they had to give them the series,” former captain Michael Clarke said on his Beyond 23 podcast.

Whether you think McSweeney should have been picked in the first place, once he was in the team he should have been given all five Tests to prove his worth because otherwise, the sample size is just too small.

The most recent decision threatens to leave a “devastated” McSweeney scratching his head as to what holds more weight with selectors — the six years of first-class cricket that got him picked or the six Test innings that got him dropped.

“I get the dream come true, and then [it] didn’t quite work out the way I wanted,” the 25-year-old told the Seven Network on Saturday.

“I’ll get my head down and get back in the nets and work really hard, and hopefully be ready to go for my next opportunity.

“I missed out a few times with the bat, and unfortunately I wasn’t able to take my opportunity.”

Bailey said it “was a difficult decision” to cut McSweeney, but “we remain confident Nathan has the ability and temperament to succeed at Test level in the future”.

What has Konstas been doing?

Clarke said selectors should admit they “made a mistake picking [McSweeney]” in the first place, simply to clear things up.

If selectors thought Konstas had shown enough in his eight first-class games before the first Test, then he should have been picked regardless of age.

Instead, with Bailey flagging Konstas’s different “style of batting” as a major reason for his call-up, it appears the teenager has flipped the script with a century in a 46-over PM’s XI game, and a BBL half-century off 20 balls for the Sydney Thunder.

Both were exhilarating knocks to be sure, but they tell us little about his suitability to face Bumrah’s wizardry that has utterly baffled all bar Head in the first three games.

Australia cannot afford to lose either of the last two Tests if it is to avoid losing the Border-Gavaskar trophy for a fifth straight time and a third successive Test series against India at home, and that pressure can cause panic in the ranks.

Whatever happens in this series, two Tests in Sri Lanka in January and February are next, with a tour of the Caribbean and a potential mid-year World Test Championship final. Then a gap before the 2025/26 Ashes start in late November when Australia will be trying to win the Urn for the fifth straight time.

Somewhere in there, or not too long after, Australia’s Test team will likely be completely reshaped.

It’s been talked about ad nauseam, but of the 12 players Australia has so far used in this series, only McSweeney, Head, Labuschagne, Alex Carey and Pat Cummins will be under 35 by the end of that Ashes series.

Khawaja will be 39 and Clarke pondered why, if selectors wanted to drop an out-of-form opener, they chose the younger one.

“Ussie’s made no runs — he’s the senior player,” he said.

“Everyone apart from Nathan McSweeney’s over 30 years of age. And high 30s.

“What happens if Usman Khawaja in two Tests retires? Does McSweeney then come back in, or does he go to the back of the queue?”

It’s a fair question to ask, considering how many batters have come and gone in the blink of an eye in the past decade.

Bancroft and Harris should be glad to have made it to double digits; Aaron Finch (5), Alex Doolan (4), Nic Maddinson (3), Kurtis Patterson (2), Hilton Cartwright (2), Callum Ferguson (1) weren’t so lucky.

We thought there was more of a long-term plan this time, but if Konstas misses out on Boxing Day, at the SCG and in Galle, will he still be there to face the West Indies? And then it’s anyone’s guess as to who will face the first ball of the Ashes in Perth.

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