Fourth one-day international, Trinidad: Australia 286-5 (50 overs) bt West Indies 219 (45.3 overs) by 67 runs
Adam Gilchrist missed out on his ninth one-day international century but his sparkling knock was enough for Australia to clinch the series against the West Indies.
The Aussies posted the third highest score in one-day internationals at Port-of-Spain after Michael Clarke followed up Gilchrist's 84 with a blistering unbeaten 55 off 40 balls.
In response the West Indies batting line-up crumbled once again as they fell 67 runs short of the Australian target.
Chris Gayle, who top scored with 84, and Brian Lara, who was caught by Matthew Hayden for 40 off the bowling of Andrew Symonds, offered the only real resistance.
The hosts' capitulation gave Australia a resounding 4-0 lead in the best-of-seven series and took their unbeaten streak in one-day internationals to 21 matches.
Afterwards Australian captain Ricky Ponting said: "We wanted to wipe the slate clean after the World Cup."
We've slowly improved in each game and today was far and away the best we've batted
Australia skipper Ricky Ponting
It was Clarke and Gilchrist who did the majority of the damage with fine contributions on a surface where the ball kept low and did not really come on to the bat.
Clarke was a little fortunate on a day when the West Indies fielding was woeful in the extreme.
He was bowled off a Corey Collymore no-ball and also survived a regulation catch which Ricardo Powell somehow spilled the ball at deep mid-wicket.
Gilchrist was finally bowled by one of Ryan Hurley's quickish off-breaks for 84. Hurley was making his one-day international debut.
The same thing happened as in the rest of the series, we were losing early wickets
West Indies captain Brian Lara
Hayden hit 44 while captain Ponting contributed 38.
By the time Lara joined Gayle at the crease, the West Indies were already 77-3, Powell, Wavell Hinds and Ramnaresh Sarwan all falling cheaply.
Lara and Gayle added 69 runs for the fourth wicket but, after Symonds dismissed Lara, the remaining batting line-up fell apart.
Marlon Samuels was the only other resistance of note, adding a sharp 27 runs off just 20 deliveries.
Jason Gillespie and Ian Harvey were the leading wicket-takers with two apiece.
Lara again blamed poor batting after the quartet of defeats.
The Windies captain said: "Only one of the top four batsmen got 80-odd runs today and
the others didn't spend much time in the middle.
"The same thing happened as in the rest of the series, we were losing early wickets."
West Indies: Chris Gayle, Wavell Hinds, Marlon Samuels, Ramnaresh Sarwan, Brian Lara (captain), Ricardo Powell, Ridley Jacobs, Vasbert Drakes, Mervyn Dillon, Corey Collymore, Ryan Hurley.
Australia: Matthew Hayden, Adam Gilchrist, Ricky Ponting (captain), Michael Clarke, Andrew Symonds, Michael Bevan, Brad Hogg, Ian Harvey, Brett Lee, Jason
Gillespie, Glenn McGrath.