West Indies was made to bat first and reached 297-6, then Sri Lanka was all out for 280 in 47 overs.
Johnson Charles and Chris Gayle gave West Indies a solid start with a combined 87, then Darren Bravo and Ramnaresh Sarwan raced along before both retired at 71 and 55 respectively in the 44th over to give others' batting time.
Sri Lanka's chase was well placed at 124-3 but few batsmen were allowed to settle, and Kumar Sangakkara's demise for 56 off 62 balls in the 32nd when he edged behind Dwayne Bravo, made the result inevitable despite a late flick from the tail.
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