Captain Steve Smith says the axing of Steve O'Keefe for the Qantas Tour of Bangladesh was made with a view to Australia's next Test series in India in 2021.

O'Keefe, who took a match-winning 12-wicket haul in the first Border-Gavaskar Test in Pune last February, was a shock omission from Australia's squad that will return to the subcontinent later this month for their first Tests in Bangladesh since 2006.

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O'Keefe's absence seemingly guarantees 23-year-old Ashton Agar will come into the XI for his first Test in more than four years, while uncapped leg-spinner Mitchell Swepson was added to the 14-man squad on Saturday.

Smith said it was "difficult to say" if O'Keefe's Test career was over, but added the decision to drop the 32-year-old was done with a view to the future.

"I thought the first Test in India he bowled particularly well and at times throughout the series he bowled well without taking the wickets we would have liked," Smith told cricket.com.au.

"Now is probably a chance to move on to someone else and Ashton Agar's going to get his opportunity.

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"(Agar) has been around for a while now and it's another chance for him to have a crack in spin-friendly conditions and hopefully he can go really well for us.

"I have (spoken to O'Keefe) and he was disappointed, which is fair enough. He understands where we're heading.

"He's getting a bit older now and our next tour back to India is in four years' time and we've got to find the right group of guys that are going to be there for that series.

"That's going to be an important one for us so hopefully we can continue to develop a few players in the meantime."

In April, O'Keefe was slapped with a $20,000 fine from Cricket Australia and suspended from next summer's Matador BBQs One-Day Cup by Cricket NSW for making "highly inappropriate comments" in an alcohol-fuelled incident following an end-of-season awards function.

It was his second alcohol-related sanction in less than a year but Cricket NSW CEO Andrew Jones, in criticising O'Keefe's axing when the squad was announced in June, said he had been told that the spinner's behavioural issues had not been a factor at the selection table.

"The feedback is it's a cricket decision," Jones told News Ltd at the time, adding O'Keefe's non-selection was "unfair" and "unjust".

"The behaviour issue was an issue but it's been dealt with. There's no double jeopardy.

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"Clearly he's the best left-arm spinner in Australia. I think the facts speak for themselves.

"Agar will be a good cricketer … but this is not a good cricket decision."

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O'Keefe's match haul of 12-70 in Pune, the best-ever figures by a foreign spinner in India, guided Australia to a surprise win in a hard-fought series they eventually lost 2-1.

The left-armer managed just seven more wickets in the remaining three Tests, a fact acknowledged by selector Trevor Hohns when the squad for Bangladesh was announced.

But his first-class record of 244 wickets at 23 is far superior to those of Agar (114 wickets at 40) and Swepson (41 wickets at 42), who were both back-up spin options in India.

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The trio's selection for the India tour meant they played a minor role last Sheffield Shield season as Victorian left-armer Jon Holland led all spinners in that competition with 50 wickets at 20 from 11 matches.

Speaking after his call-up to the Bangladesh squad on Saturday, Swepson conceded he had been surprised to learn that O'Keefe had been left out.

"'SOK' (O'Keefe) bowled really well in India and he's done well in Shield cricket for a long time now, so I was actually very surprised to see him not get the nod again," the Queenslander told cricket.com.au.

"But that's obviously all up to the selectors."

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