Five things we learnt from the Windies v Australia T20s

1) Mitch Marsh might bat at three in the World Cup

Before departing Australia's shores, Aaron Finch made it clear that those who performed against West Indies (and Bangladesh next month) could put pressure on the absent first-choice players for World Cup spots. Mitch Marsh could hardly have responded to that invitation more emphatically, claiming the rare double as the visitors' leading run-scorer and wicket-taker for the series. The only question now is where he bats when Steve Smith (pending recovery from an elbow concern), David Warner, Glenn Maxwell and potentially Marcus Stoinis return to this team. Marsh has spent most of his career batting further down the order and could return to a middle-order role with added confidence, though both Adam Zampa and Matthew Wade have suggested he could remain at three. What will please selectors the most is an encouraging improvement against spin bowling, against which his strike-rate stood at just 99.34 in T20s (domestic and international) compared to 146.97 against pace prior to the Windies series. Over the five games against the reigning T20 world champions, his strike-rate against spin was 133.80 and 169.86 to pace.

2) Australia remain vulnerable against spin, particularly wrist-spin

Apart from the obvious, what do Adil Rashid, Ish Sodhi and Hayden Walsh all have in common? The three leg-spinners were the leading wicket takers in each of Australia's T20 tours since the start of the pandemic. That may have been a lesser concern for Finch and Justin Langer's men if this year's upcoming World Cup was being played on the bouncy pitches of Australia. But the fact the main group stage and finals are being held on just three grounds in the United Arab Emirates, which will be worn down by 31 Indian Premier League games played immediately prior, means spin will be king as the tournament goes on. In 2016 for the last World Cup in India, six of the eight leading wicket takers were spinners. The Aussies have admitted they were not sufficiently prepared for the threat of Walsh in the Windies series, but there's a significant body of evidence to suggest there is a team-wide shortcoming against wrist-spin. The return of Smith, Maxwell and Warner, Australia's most experienced short-form batters on the subcontinent, will help but their World Cup opponents will no doubt continue to look to exploit the weakness.

3) The search for the elusive 'finisher' goes on

The imperiousness of Russell during the series left Australia with two separate headaches. The first is how their bowlers are going to stop him when they face him again in the group stage of this year's World Cup. The second is why they cannot find someone who can do a reasonable impression of his incredible hitting ability. When the series was live, the Aussies hit 12 sixes between them; Russell hit eight by himself in those first three games alone. The explosive allrounder is, of course, the gold standard in terms of late-overs power hitters, but the Aussies struggled to find even silver or bronze in their middle order against the Windies. None of Josh Philippe (who made 1 and 13 from No.4 before being dropped and then recalled in his familiar opening spot), Moises Henriques (95 runs at a strike-rate of 123.37 in five innings), Ben McDermott (2 and 7 from No.6 before suffering a quad injury), Alex Carey (13, golden duck and 9), Ashton Turner (24 and 6 from No.6 before being dropped) or Dan Christian (10, 9, 1no and 22no) advanced their cases. It is worth noting, however, that Finch conceded the top-order did them few favours in this series. "When you try and stamp your authority on a game when you’re still trying to find your feet in international cricket, it can be tough," he said. "I’m not too critical of them to be honest."

4) Australia's bowlers will be better for the run

Mitchell Starc gave a revealing insight after his superb final over to Andre Russell helped Australia notch their only win of the series. The paceman had earlier copped the full force of the West Indians in going for 89 runs in the opening two games and admitted his plans in the first match "weren't right and we addressed that," adding, "Personally, (I) went back to things that were strengths of mine". In a five-game series, players can make those early adjustments after getting a look at their opponents. They do not get the same luxury in a World Cup, where one or two poor group-stage games can spell an early flight home. In the scheme of things from a bowling point of view, the Aussies are likely to be content with how they fared against the Windies, especially with Pat Cummins absent. The leading men in his absence, Starc and Adam Zampa, had standout moments, as did Cup hopefuls like Andrew Tye and Mitchell Swepson. Josh Hazelwood, who only had nine T20Is to his name before the series, showed he can be effective in the right circumstances, as did allrounders Marsh and Dan Christian. Getting a solid run of consistent T20 cricket in the coming months will only help with finding the same fluency in the format the West Indians exhibited. And with larger-than-usual squad sizes to be permitted at this year's World Cup, having a pool of bowlers available to call upon depending on opposition match-ups will be crucial.

5) Australia's short-form depth has been given a reality check

There were some positive signs on the bowling front with Tye, Jason Behrendorff and even Riley Meredith, despite an expensive series, giving glimpses of their ability. But the struggles of the batters did not paint a flattering picture of Australia's talent pool beneath the top flight given the bulk of the squad have been the leading players in the KFC BBL. Consider that a second-string England ODI side swept Pakistan this month and a similarly weakened Indian outfit will attempt to do the same against Sri Lanka in the coming days. West Indies admittedly have a much stronger and experienced side than both Pakistan and Sri Lanka, but it is worth noting the Windies, like the Aussies, were not at full strength either. Captain Kieron Pollard and his predecessor Jason Holder missed the entire series, while Dwayne Bravo, Shimron Hetmyer, Evin Lewis and Obed McCoy (all of whom were match-winners in the series for the hosts) missed multiple games. The conversation about depth is not a theoretical one; as has been shown in sport all over the world during the pandemic, there is always the potential that numerous players could miss games at short notice.

Qantas Tour of the West Indies 2021

Australia squad: Aaron Finch (c), Ashton Agar, Wes Agar, Jason Behrendorff, Alex Carey, Dan Christian, Josh Hazlewood, Moises Henriques, Mitchell Marsh, Ben McDermott, Riley Meredith, Josh Philippe, Mitchell Starc, Mitchell Swepson, Ashton Turner, Andrew Tye, Matthew Wade, Adam Zampa. Travelling reserves: Nathan Ellils, Tanveer Sangha.

West Indies T20 squad: Kieron Pollard (c), Nicholas Pooran (vc), Fabian Allen, Dwayne Bravo, Sheldon Cottrell, Fidel Edwards, Andre Fletcher, Chris Gayle, Shimron Hetmyer, Jason Holder, Akeal Hosein, Evin Lewis, Obed McCoy, Andre Russell, Lendl Simmons, Kevin Sinclair, Oshane Thomas, Hayden Walsh Jr

T20 series: West Indies won 4-1
(all matches at the Daren Sammy Cricket Ground, St Lucia)

First T20: West Indies won by 18 runs

Second T20: West Indies won by 56 runs

Third T20: West Indies won by six wickets

Fourth T20: Australia won by four runs

Fifth T20: West Indies won by 16 runs

ODI series
(all matches at Kensington Oval, Barbados)

First ODI (D/N): July 21, 4.30am AEST (July 20, 2.30pm local)

Second ODI (D/N): July 23, 4.30am AEST (July 22, 2.30pm local)

Third ODI (D/N): July 25, 4.30am AEST (July 24, 2.30pm local)

* Details of five-match T20 tour of Bangladesh are yet to be announced by the Bangladesh Cricket Board. Tours are subject to agreement on bio-security arrangements and relevant government approvals.