David Warner scored an unbeaten half century as Australia romped to a six-wicket thrashing of West Indies in their opening Tri-Nation Series day-night game at the Guyana National Stadium on Sunday.

Warner's 55 not out saw Australia home with almost 25 overs to spare after the West Indies earlier collapsed from 50 for one to 116 all out from 32.3 overs.

Australia then wasted little time in getting to the modest target, Warner anchoring the effort to ensure a victory that was never in doubt despite the loss of three wickets for seven runs with the end in sight.

The emphatic victory earned Australia a bonus point to move ahead of the West Indies in the three-team standings before Tuesday's game at Providence against South Africa.

West Indies had beaten South Africa by four wickets on Friday. Each team will play the other thrice and the top two in the table will contest the final on June 26.

SCORES IN BRIEF

WEST INDIES: 116 all out in 32.3 overs (Charles 22, Brathwaite 21; Zampa 3-16, Lyon 3- 39, Starc 2-37)

AUSTRALIA: 117 for 4 in 25.4 overs (Warner 55 not out, Khawaja 27; Narine 2-36, Benn 1-21)

Result: Australia won by 6 wickets.