Australia is on the cusp of victory thanks to a remarkable new ball spell from Josh Hazlewood and a gritty century from Travis Head. 

Here's the five quick hits from day one at Adelaide Oval.

1. Green too high at number four?

It is admittedly a (very) small sample size, but the second piece of the new Australian batting puzzle showed signs that it wasn't fitting particularly well.

After Steve Smith made just 12 opening the batting for the first time, Cameron Green made just 14 before feathering behind at number four.

"I know Green is a talented player," said Jim Maxwell on ABC Radio.

"Travis Head's form, in any form of cricket, entitles him to be coming in at four in this team."

Head has batted in every position from first to sixth in Test cricket — apart from at four.

He has batted most often at five in Tests, and averages most there as well, 44.87.

Green, meanwhile, has only previously batted in the sixth or seventh position for Australia in the long-form game, although did score 96 at four for Western Australia in the Sheffield Shield match against Queensland at the Gabba in November.

2. Fifth time lucky to snare Marsh

The lack of carry to the slip cordon was causing plenty of concern throughout the first innings of both sides.

And that lack of pace was evident when Marsh edged towards the slips not once, not twice, not three times even. But four times the West Indies found the outside edge of the West Australian all rounder and all four times they fell short.

So, to the tourist's credit, they made some adjustments, bringing a helmeted Justin Greaves at third slip in far closer than the rest of the cordon.

And it worked a treat.

Kemar Roach squared Marsh up, the edge flew low to Reaves, who took an excellent catch.

3. Travis Head tons up

Coming into this summer, there had been plenty of disparaging commentary about the standard of the opposition heading to these shores.