Hayden Walsh went wicketless as Ireland piled on 237/9 in the 2nd ODI but his heroics in a thrilling match would come with the bat.
West Indies’ chase of 238 looked over at 148/7 with skipper Kieron Pollard (40) back in the pavilion too.
But Walsh, who has a List A and First Class 50 to his name, got to work.
He hit four boundaries in a patient knock of 46 not out from 67 balls.
Walsh got support in the lower order from Khary Pierre (18) and Alzarri Joseph (16).
After two dot balls in the final over, Sheldon Cottrell took a single to get Walsh back on strike – it almost resulted in a run out but after a look from the TV umpire, it was given not out.
Next ball, Walsh hits a full toss and runs a single and again, there was almost a run out.
Cottrell then hit a full ball over cover for six to win with one wicket and one ball to spare.
West Indies have now taken an unassailable 2-0 lead in the three match series.
Joseph, who earlier took 4/32, was named Man of the Match.