Takeaways: Batting under scrutiny, Green's evolution and masterful bowling quartet

Josh Hazlewood's off stump flies out of the ground. He stands almost motionless, as does Steven Smith at the non-striker's end having carried his bat for 91. Shamar Joseph and his delirious team-mates are somewhere over at deep midwicket. The home season for Australia's men's Test team had come to the most extraordinary conclusion - their first home defeat under Pat Cummins and the first to West Indies since 1997.

Australia have played some excellent cricket at times this season, finding ways to produce hard-fought wins, but there was also a fallibility that is not often on show on home soil (at least, that is, unless India have been the visitors in recent times). The white ball now takes over for the next three weeks before the Test team comes back together in New Zealand. After a season that produced far more drama than had been expected, here are some key talking points.

At various times across the five home Tests, Australia had suffered collapses of 6 for 68, 4 for 16 and 5 for 10 before the match-defining slump of 8 for 94 at the Gabba. On other occasions the top order had been left in uncertain positions against visiting attacks that defied lowly pre-tour billing. There were just two individual hundreds - David Warner at Perth and Travis Head in Adelaide - albeit Mitchell Marsh fell twice in the 90s and Smith was close to a brilliant century in Brisbane.

Still, it's a low return on home soil. In a home season of at least five Tests, not since 1996-97 have they scored as few centuries. Head became just the third Australian to bag a king pair in Test cricket - and collected another first-baller in Melbourne - to counter the superb Adelaide century. There is a belief, backed up by numbers, that batting has become tougher in Australia in recent seasons although conditions have not been unplayable.

"First and foremost you don't want to put yourselves in those [difficult] positions, no doubt about that," head coach Andrew McDonald said. "Think the context around that is the wickets have been a little tricky. No doubt, we want to get better at that as well. Some batters that will sit in the rooms, looking back on the summer and a few missed opportunities. Was it decision making? Was it good bowling? These guys have an appetite to improve the whole time."

Marnus Labuschagne made just 19 runs in four innings against West Indies, having ended the Pakistan series suggesting he was finding his best form again. He fell hooking in Adelaide and was then challenged outside off stump in Brisbane. Overall, a Test average which stood at 63.43 is now at 50.82.

"I think the positive within that [is that] the law of averages suggests that he's due for a couple of bumper Test matches and series," McDonald said. "So we've got full trust and faith in the way that he goes about his preparation, the way he goes about his innings.

"He's been undone by certain plans at times, so there's no doubt that we will get into that he does get busy and get back to work. We've got full confidence in his ability to rebound. He's a quality player. There's no doubt that you're going to go through some lulls of form if you want to call it that."

Nathan Lyon did little to dampen the expectations around Cameron Green. "I actually enjoy seeing him bat at No. 4 and I feel like he could be the next Jacques Kallis of international cricket at number four," he said after the third day at the Gabba.

Much of the focus was on Smith's move up the order, but with an eye on the longer-term future of Australia's top order Green's return at No. 4 was equally significant. It has always been viewed as his natural home, although it was largely thought it would come with Smith's retirement. The desire to get Green back in the side was central to the debate around replacing Warner.

There were promising signs in the second innings at the Gabba before he played on against Shamar Joseph's extra bounce to begin Australia's collapse. It followed his work with the ball on the oppressively hot third day, with McDonald and Cummins singling him out as the pick of the attack. "Felt like it could have been anything," McDonald said of his return of 1 for 37, during which he was particularly impressive round the wicket to the left-handers.

"Think if you've watched his innings at international and Shield level, he can start slow, there's no doubt about that, and it's something he's working on," McDonald added on Green's batting. "Takes him a while to get his movements in sync at times. That's no different to any other batter, but once he's up and going it's a pretty good sign."

Among the debates around the post-Warner future has been the referencing to Australia's best six batters and the hierarchy that now follows. Matt Renshaw is inked in as the seventh having been preferred in the squad to face West Indies ahead of Marcus Harris and Cameron Bancroft. He is now in pole position to replace Usman Khawaja when that moment arrives, although it could still be a few years away.

It has left Harris and Bancroft in limbo, particularly the latter after his success at Sheffield Shield level. Cummins contacted the pair directly to reassure them that they had a Test future. But it also felt significant that chief selector George Bailey name-checked Aaron Hardie and Nathan McSweeney as players they were impressed by. After the way the West Indies series finished, there will be some added scrutiny on the incumbents, but this new order will be given a chance to settle.

"We're not in the in the mood to change the batting order. We feel like as a collective that that unit will be able to have success over multiple Test matches," McDonald said. "I suppose if you look at the irony of it all, the question marks were on Steve Smith and Cameron Green and they were our two best-performed batters [on Sunday]. But we see our batting as a collective. There's going to be people that fail within that at times, there's going to be people that succeed. It's all hands on deck, but we feel as though that order with the way it is, they complement each other."

Each of Australia's four frontline bowlers enjoyed a landmark this season: Lyon's 500th, Cummins and Hazlewood reaching 250 Test wickets and Mitchell Starc going past 350 to close in on Dennis Lillee. They are a great bowling attack and, at times, had to paper over some cracks in the batting. But there remains the lingering question about when those in reserve will get their opportunity. It's not beyond the realms that this quartet complete seven Tests in a row by playing the two games in New Zealand.

Scott Boland averages 12.21 in home Tests although struggled more during the Ashes in England. The selectors know what they will get from him if and when they need to call him back. In terms of the future, it's Lance Morris who many are waiting with bated breath to see unleashed in Test cricket. He will feature in the ODIs against West Indies but the selectors are happy to wait for a spot to naturally open up in Test cricket.

"Think the bowling unit getting five Test matches in, getting through and they've all pulled up well again, that's an incredible success for the same attack to play throughout the summer," McDonald said. "That bodes well for New Zealand."

The Test series against New Zealand begins in Wellington on February 29. It will be Australia's first Test trip across the Tasman since 2016 and contests between the two always come with an edge (even if the head-to-head is heavily in Australia's favour), but they now take on added significance. If New Zealand beat an understrength South Africa 2-0 - and recent days have told us not assume anything - then the series could be key to the World Test Championship standings. Australia would not have factored dropping points at home this summer.

"We've dropped one [match] at home which means we probably need to make one up overseas," McDonald said. "That's the wonderful part about the World Test Championship."

Following the New Zealand series, there is a long break in Australia's Test schedule until next November and the arrival of India. There is a lot to play out before then, but it is shaping as another epic tussle. The last few days at the Gabba has given it a lot to live up to.