"If you can knock Chris Gayle over early…" mused Australia's captain, George Bailey, ahead of their World Twenty20 semi-final against West Indies. And if you can't, George? If you can't, the night will end in the way you must have secretly feared it might, with the entire West Indies team, Gayle at the centre, with grin as broad as his broadest of bats, dancing to "Gangnam Style".

"Gangnam Style", by the South Korean rapper PSY, is a satire of life south of the river in Seoul, where cool and style are held to predominate. But now there is a PS to PSY and it has been provided by the West Indies cricket team who are threatening to turn the dance into a story of Caribbean resurgence.

"It just happened," Gayle said. "It wasn't really planned. That's me. Depending on what type of mood I'm in, I do something crazy. It's a good dance."

Twenty20 might be hard to predict, but somehow, out of it all, we have got a fitting final: Sri Lanka, increasingly powerful as the tournament progressed, symbolising the growing confidence of a nation freed from terrorist war, against a West Indies side which was strongly fancied before the tournament began and which put its inconsistencies behind it to produce an emphatic performance when it mattered.

Australia did not get Gayle out, but they did manage to limit him to 41 balls, little more than 30% of the strike, which on many nights would count as a job well done. For large clumps of the innings, he stood at the non-striker's end, under-utilised, overlooked. But those 41 balls were enough for him to make 75 not out. He does not need long to make an impact.

Gayle's career has been that of a rebel - "Me talk with my mouth and me talk with my bat," he once observed in an unfavourable critique of West Indies cricket - but in this tournament his desire to contribute to his team's success has rarely been stronger. He met Mitchell Starc, Australia's dangerman, with respect; he was as selective in his strokeplay as he surely ever has been in T20; he even looked, goddammit, as if he was intent from the outset to try to bat through the innings.

If he bestrode the scene, this was far from a solo performance. As he stood at the non-striker's end, a hulk of a man with chain lolling idly over his maroon shirt, he must have liked what he saw. Marlon Samuels was a polished understudy (the Yohan Blake to Gayle's Usain Bolt), Dwayne Bravo produced his most vigorous innings of the tournament, and the final partnership between Gayle and Kieron Pollard was a rumbustious affair, 65 from 25 balls, between two outrageously powerful men who did not much fancy running and did not need to.

He was caught once, off Xavier Doherty, but the catch was held by a policeman 20 yards beyond the boundary boards, lurking behind the sponsor's motorbike. That is a pretty nifty fielding position for Gayle when he is in full flow. Australia's only hope was that under Sri Lankan law, a clean catch would allow the policeman to commandeer the bike and ride onto the square to arrest Gayle for a public order offence.

Australia's only hope was that under Sri Lankan law, a clean catch would allow the policeman to commandeer the bike and ride onto the square to arrest Gayle for a public order offence

He has one chief hitting arc, in the general area of long-on, but Australia's bowlers, like many before them, could not prevent him from insouciantly depositing the ball in that direction. His most imperious blow came against the offspin of David Hussey, who had been called up for his first game of the tournament, and whose reward was to disappear into the second tier of the stand. The blow was measured at 104 metres, the joint-longest six of the tournament.

By then, Gayle had received treatment after being winded. He was feeling short of breath, his heart pumping, enough to slightly disturb him, which brought him down to Pollard's speed between the wickets. They lumbered a two through mid-on with the reluctance of a couple of old stagers in a club match, but how they hit. Pollard's assault on Doherty in the last over was brutal. The more jauntily Doherty tried to run up, the more his face clenched in concentration, the more his left-arm spin pitched, for him, in the most inconvenient places.

It was Pollard, not Gayle, who played the most outrageous shot of the night, a 93mph yorker from Pat Cummins which Pollard dug free with such strength that the ball scooted around the ground and split midwicket and long-on. Just getting a ball like that off the square is an achievement.

There is something about Australia's attack which delights West Indies. It is the sort of fixture where sixes rain down and they need to buy in extra fireworks for behind the scoreboard. They have taken Australia for two of the three highest scores in the tournament, also making 191 for 8 against them in the qualifying stage, only to lose on Duckworth-Lewis.

Gayle took some time checking things out. It is rare that he bats with such a strong sense of care and concentration. He begins every innings by crouching on his haunches, not as much an exercise routine as a feline stretch, an attempt to settle his mind, get into the zone. For nearly five overs, the Australian attack was cased and the tension in the crowd was palpable when he finally awoke to crash Shane Watson for six over extra cover.

In one shot, the mood of the game changed. Gayle was on the move, the x-man was about to happen. Fourteen times, the West Indies cleared the ropes, fireworks studded the night sky and the West Indies batting was liberated.

They have one more challenge, but Sri Lanka, wonderfully marshalled, brimming with confidence and originality, and yearning for their first victory in a major tournament since 1996, will be the biggest challenge of all.

David Hopps is the UK editor of ESPNcricinfo