It was an action-packed day one of the first Test in Wellington. Here are five things we learnt.

1. Peter Siddle is far from done

​Who said Peter Siddle was a spent force at Test level? The Victorian produced one of the best performances of his career on the first morning of this match with figures of 12 overs, five maidens, 3-37 - and 16 of those runs came off his last over! At one stage, the veteran bowled 26 dot balls in a row as he formed one half of the Australian wrecking crew that ripped New Zealand's top order apart in the first hour.

2. Josh Hazlewood is only getting better

Josh Hazlewood was the other half of that wrecking crew and was the more impressive member of the duo. The talented 25-year-old picked up a team-best 4-42 - the fifth four-wicket haul of his fledgling 16-match career and the third in his last five matches. If there were any doubts over this bloke's bona fides as a future leader of the country's fast-bowling group, then surely they are gradually dissipating. He seems to be getting better with every match.

Early breakthrough: Josh Hazlewood took the wicket of Tom Latham in the third over. Photo: Getty Images

3. Ian Chappell's adage doesn't apply to greentops

Ian Chappell's famous saying is: "Nine times out of 10 when you win the toss, bat first; on the 10th occasion think about it, then bat". But the reverse is true when confronted with the kind of greentop that Australia and New Zealand were presented with in Wellington and Smith agreed as he won the toss and sent the Kiwis into bat. It proved a masterstroke as the hosts were dismissed inside 48 overs. In fact, 12 wickets fell in the first 51 overs!

Brendon McCullum and Steve Smith toss the coin. Photo: Getty Images

4. Catches win matches

However, one adage that rings true at all grounds and all conditions is "catches win matches". And New Zealand learned the true nature of that adage the hard way. When Smith edged Bracewell to Craig at second slip in the 13th over it looked as though the Australian danger man was headed back to the pavilion. But Craig crucially grassed it, giving Smith another life. The fact Smith was on 18 at the time of the drop, and was eventually dismissed for 71 in an innings that featured 10 fours and a six, added insult to injury for the Kiwis. The skipper was able to compile a crucial 126-run partnership with Usman Khawaja to steady the ship and put the Aussies in control after they were in the precarious position of 2-5.

Mark Craig and Tim Southee lament Mark Craig's dropping of Steve Smith. Photo: Getty Images

5. New Zealand bails weigh a ton!

Mitch Marsh could barely believe his eyes when one of his deliveries rebounded off Mark Craig's elbow and back into the stumps with significant force yet failed to dislodge the bails! In fact, the bails didn't even budge! It looked as though metal stumps usually associated with backyard cricket were being used!