West Indies beat Australia in Eleven11

AP ©

Even Ricky Ponting has admitted he had no idea how to attack an 11-over match.

The West Indies claimed their first victory of Australia's Caribbean tour in extraordinary circumstances after triumphing by seven wickets in the shortest-completed Twenty20 international in history.

Persistent rain reduced the match to essentially an Eleven11 contest.

But the weather did nothing to detract from the spectacle as Xavier Marshall and stand-in skipper Dwayne Bravo set alight a gloomy Kensington Oval to rocket an inexperienced Windies - missing Chris Gayle, Ramnaresh Sarwan and Shivnarine Chanderpaul - past Australia's competitive 3-97 with 11 balls to spare.

"That's the shortest game of cricket I've ever played," said Ponting of 20.1 over match.

"We didn't really know how to attack an 11-over game.

"We've been setting ourselves for the last couple of days to get ready for a 20-over game, and then all of a sudden we were hit with an 11-over game."

Ponting conceded Australia all but lost the match in the first two overs of the Windies innings as Marshall ran riot to have the 10,000-strong crowd pumping.

The confident 22-year-old opener belted Brett Lee for six from the first ball of the run chase, before dispatching Mitchell Johnson for two more the following over - the last of which cleared the roof of Greenidge and Haynes Stand and went out of the ground.

The home side's 50 came up in just 2.5 overs.

And while Marshall departed soon after for an amazing 36 off 15 balls, the damage had well and truly been done as Bravo (28 not out) went on to seal victory with another monstrous six over long on off Shane Watson (1-17).

Marshall claimed the man of the match award after earlier taking a brilliant catch tip-toeing inside the boundary during the Australian's innings.

Earlier, debutants Luke Ronchi (36 off 22) and Shaun Marsh (28 off 22) gave Australia a flying start with a 57-run opening stand before the touring side was pegged back by teenage quick Kemar Roach (3-29 off three overs) and Bravo (1-12 off two).

"Obviously the shorter the game goes, the bigger the difference a single over or a single shot makes," Ponting said.

"I thought we did a reasonable job with the bat. We were talking about 100-110 being a pretty good total. But our first two overs were probably the difference in the game."

The result sets up a tantalising five-game one-day series starting in St Vincent on Tuesday, with Bravo claiming the Windies would draw great confidence from the result after going down 2-0 in a hard-fought three-Test series.

"It will do our confidence well as a team," said Bravo, whose side today featured three players making their international debuts, including Bajan Roach who has played just four first-class games.

"Once again we go down in history. This is the first Twenty20 (international) in the Caribbean and it's nice to come out with a win.

"I'm happy to lead the team, it's a very young side ... and I'm very happy they could make a name for themselves."

Australia play a day/night tour match against the University of West Indies Vice-Chancellor's XI in Barbados on Saturday (Sunday 4am AEST).

Andrew Symonds (back spasms) and Brad Haddin (broken finger) will again be rested from that match, but Ponting said both should be fit for the first one-dayer.

Before today, the previous shortest Twenty20 match had been a 13-over clash between South Africa and the West Indies last December.