The target is 185. Australia are 160 for 4 after 18 overs. Who do you want at No. 6 to finish that chase?

As Aaron Finch's side travels to the West Indies then onto Bangladesh for 10 T20Is the question of who fills the middle-order finisher position(s) heading into the T20 World Cup remains one of the key areas they need to answer.

Once again this won't be a full-strength Australia side with numerous withdrawals over bubble fatigue. The batting has been especially hit without David Warner, Steven Smith, Glenn Maxwell and Marcus Stoinis.

However, uncertainty over middle-order batting positions (for the reference of this piece that will cover Nos 5-7) has not just crept up on Australia in recent months. It has been the area of the side that has proved the most difficult to settle upon.

Whose turn is it next?

Since the 2016 T20 World Cup, where Australia did not get out of the group stage, they have used 25 players across those three middle-order slots. There will always be an element of batters moving through positions given the various scenarios created in T20 matches, but only Sri Lanka, with 30, have cycled through more options so far between World Cups.

Stoinis, Alex Carey - who is no longer a starter in the XI - and Ashton Agar have had the most regular opportunties and while Stoinis' numbers are decent it would be a leap to say the solution has been found.

It is the strike rate Australia have managed from those positions which highlights the issue. Since the last T20 World Cup the Nos 5-7 have struck at 118.53 putting them between Ireland and Bangladesh at the lower end of the table (with a cut-off of 20 matches). Hong Kong, Zimbabwe, UAE, Oman and PNG are the other teams below them.

Another way to look at it is the balls-per-boundaries and per-six from that same group of middle order positions. Again, Australia do not stand up well. They are bottom on balls-per-boundary among the current top 10 teams of the rankings and only Bangladesh have a worse balls-per-six ratio.

Square pegs, round holes?

One of the issues for Australia's selectors is that they have largely put players out of position for those middle-order roles. Most of them are top four batters in the BBL which is logical for those clubs who want the best out of those players but does not give them a proper chance to adjust to what is a very specialist and skilled role lower down. That was shown by Carey's difficulties adapting down the order.

"If you ask most batters around the world, batting later in the innings or it might not so it is a difficult role mentally to keep backing up." Carey said from St Lucia. "It's either hit or bust and we've seen around the world the best teams have probably got a hitter at the death. There's probably only a handful of really good finishers around the world. It's a specialist position and every team would love to have a powerhouse coming in late but you also rely on your top order to set you up and score the big runs."

It was a subject Dinesh Karthik, the India wicketkeeper-batter, recently discussed in an interview with ESPNcricinfo. He was referencing the India team, but the point he makes is relevant to Australia.

"In the T20 format, it is a far more niche slot, something that you need to have done over and over again," he said. "And that's why you have the Pollards and the Russells or the Dhonis, who have done this over a period of time, who have helped play so many of these impact innings.

"You don't want to go to a World Cup with people who have batted in the top four consistently and throw them in at five, six, seven and expect them to do well."

The numbers from the last two seasons of the BBL would suggest that Mitchell Marsh is worth considering, with a high overall strike-rate and very strong numbers at the death, although at international level over the last two years he has struck at barely a run-a-ball.

Maxwell, as ever, is an interesting debate. Such is the dynamism he brings as a batter in T20 that putting him below No. 4 can feel a waste, but in the last two years of BBL he has a strike-rate of 160 at No. 5.

It is also worth remembering that as of last season the BBL had the Power Surge available after the 11th over of an innings that will impact the strike-rates of those involved. Although the Surge was widely accepted as the most successful of the innovations, one of the issues raised was that it is not a condition used at international level.

Balance of the side

In recent times, Australia have gone down the route of selecting five specialist bowlers - often including two spinners - which has put Agar at No. 7. When the team clicks, as it did during the 2019-20 home season, the middle order was barely needed - Carey, for example, did not get a bat during the six home games that summer - but Agar's batting numbers at international level have suggested a lack of power ideally needed.

There have been warning signs about the middle order: during the run of success they lost to South Africa in Port Elizabeth when they failed to chase 159 from 98 for 1 in the 13th over and last year contrived to lose against England in Southampton.

Finch has indicated they will look to alter things in West Indies, but the other issue which impacts who fills the middle-order positions is what Australia do with their wicketkeeper. Since Carey was ditched at the end of the series against England last year, Matthew Wade has taken the gloves and most of the time opened the batting. However, that has been filling in for the absence of Warner; at the World Cup he will resume his partnership with Finch. Steven Smith then has to slot in at No. 3 followed most probably by Maxwell at No. 4. So, again, Australia look like needing their wicketkeeper to bat in the middle order.

It might be that Wade has to take one of those positions by default; Australia need someone behind the stumps and he is viewed as a versatile and selfless player (as demonstrated by opening the batting in the Tests against India). Though Wade has done it at times during his career, it would be another case of a player out of his natural position: 73 of his 121 T20 innings have been in the top three and he has batted at No. 4 or lower only three times in the last three years - all for Australia. It could be that a few options are cycled through during the matches against West Indies and Bangladesh.

One name who isn't in the squad but has been gaining traction is Josh Inglis of Perth Scorchers. He has had a lot of success at the top of the order, which is where he is currently batting for Leicestershire in the T20 Blast, but significantly has also adjusted to the middle order albeit still no lower than No. 4. He is, however, considered an excellent player of spin.

Hiding in plain sight?

Those of you who have reached this far may well be thinking of one name: Dan Christian. In the last few weeks he is suddenly back in the frame having not played for Australian in four years. With the withdrawals from the squad for West Indies and Bangladesh, Christian now has the chance to make a last-ditch bid for the World Cup squad.

His credentials have been endorsed by his BBL coach Greg Shipperd who talked of his "fearless" approach. Crucially, too, he is a middle-order batter. And, even if three consecutive scores of 1 in the aborted IPL are perhaps a cautionary note, his recent BBL numbers are even more impressive than the table earlier in this piece which were pulled down by his 2019-20 campaign with the Renegades.

"He's got a unique skill set as a strong finisher through the middle and at the back-end with the bat," Shipperd said.

Even with the significant number of absentees it would be strange to recall a 38-year-old if he wasn't a serious chance of being involved in the T20 World Cup. Before departing, Finch gave a strong indication Christian was at the forefront of their thoughts amid the rethink of the make-up of the team.

"He's someone who is so dynamic and we saw the impact he had especially towards the business end of the Big Bash last year, he came in and had a high strike-rate from ball one, he's explosive with the bat, has tricks with the ball, he's experienced, he doesn't get fazed and he's a brilliant fielder," Finch said. "Dan's a superb player and an unbelievable competitor."

Is he the man you want walking out with 25 to win in two overs? The next few months will tell us.

With inputs from Gaurav Sundararaman

Andrew McGlashan is a deputy editor at ESPNcricinfo