Australia's hopes of reclaiming the No.1 ranking are in the balance after Brendon McCullum hit the fastest century seen in Test cricket, knocking the great Viv Richards out of the record books.
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McCullum hits fastest Test hundred
Brendon McCullum put a smile on the face of New Zealand cricket by hitting the fastest Test hundred of all time against Australia on Saturday. Vision courtesy Fox Sports.
Australia had been on track for another rout of New Zealand's batsmen but were shellshocked by McCullum, who made the most of two lives from James Pattinson to smash a record that has stood for nearly 30 years.
In reply to New Zealand's frantic 370, Australia were 1/57 at stumps and walking a tightrope in a match they cannot lose if they are to return to the top of world cricket.
McCullum, playing in his final Test, was given lives on 32 and 39, the latter from a no-ball by Pattinson that would have been undetected had it not produced a wicket. Pattinson's error cost his team 106 runs - already a heavy price but one that may seem even heftier later in the match.
The Black Caps captain had said on match eve that the Hagley Oval greentop could be "one of those times when fortune favours the brave". And so it proved.
New Zealand's innings could be divided into three phases. Before McCullum had batted, while he was at the crease and when he was back in the pavilion. The latter two were played in fast forward, the button pushed as soon as McCullum came in.
The Black Caps were languishing at 3/32 in the 20th over but scored at nearly nine an over in the 124 minutes McCullum held court.
For just over two hours, the retiring star had a capacity crowd at Hagley Oval eating out of his hands - and an Australian XI wishing he had already bowed out. They had welcomed him to the middle with a guard of honour only for McCullum to treat their bowlers with disdain.
To describe McCullum's as a fairytale century would not be apt because fairytales are not meant to be this brutal. Nor was this a once-in-a-lifetime innings for McCullum because he has played several of them against the white ball - though never on a wicket as lively as this.
"On that wicket the feedback from the boys was that at any stage a ball could have your name on it," McCullum said.
"What we were able to do was knock them off that difficult length on the top of off stump. If you're trying to hang in there at the top of off stump, geez you're in big trouble, I reckon.
"That was our thought process, it's nice when things come off."
This was far from a textbook knock from McCullum, who walked down the wicket repeatedly to the quicks and often backed outside leg to play outrageous cross-bat swipes.
It is hard not to be wowed no matter how you break down McCullum's 145. His first 50 came off 34 balls, his second 50 from only 20. Test cricket's fastest half-century came off 21 balls.
McCullum's 54-ball century broke the previous mark of 56 owned by Richards and Pakistan's Misbah-ul-Haq, the latter's also coming against Australia. The difference of two balls may seem narrow but is akin to breaking Usain Bolt's 100-metre world record by 0.34 seconds.
This was indeed a bolt from the blue for McCullum. He had not made an international century in any format in 13 months; prior to Saturday he had hit only one ton in 28 Test innings against Australia, passing 50 only four times.
He had also turned into Mitchell Marsh's bunny, dismissed five times in 37 balls since November. So it was telling then that in the first over he faced from Marsh, he belted the all-rounder for 21 runs.
McCullum's pyrotechnics were not in keeping with how difficult the Kiwi top order found the going. Kane Williamson, one of the best players in the world, faced 10 fewer balls than McCullum to make seven.
Australia's bowlers played the first Test entirely on their terms but had no answer once McCullum took the challenge to them. If they had their time again they would no doubt have adopted an approach more in keeping with one-day cricket. Remarkably, not one yorker was fired at McCullum's stumps.
McCullum's bravado inspired Corey Anderson, whose 72 off 66 balls appeared sedate next to his skipper.