Coulter-Nile was ostensibly selected for his seam bowling but his previous best score of 34 in 56 internationals paled into insignificance when he crunched an extraordinary 92 off 60 balls.
Steve Smith had earlier anchored the recovery after the rest of the top order had folded in the face of sustained West Indies hostility, as his 73 was the ideal foil to some incredible hitting from Coulter-Nile.
Smith seemed poised to top-score himself but he exited the field to predictable jeers following a truly remarkable catch from Sheldon Cottrell that was just as jaw-dropping as Ben Stokes' grab last Thursday.
Coulter-Nile's late burst – which overtook Heath Streak's 72 as the highest score by a number eight in the tournament's history – seemed inconceivable when Australia wilted to early pace and bounce.
The Windies adopted a similarly aggressive mindset to the one that had blown away Pakistan for 105 after they asked Australia to bat first, and the tactic paid rich dividends early on.
Aaron Finch and David Warner were both dismissed for single-figure scores while Usman Khawaja was pinned on the grille of the helmet and his body before Andre Russell had him caught behind, with Shai Hope taking an excellent catch diving low to his left.
Glenn Maxwell failed to trouble the scorers before top-edging a hook off Cottrell to Hope, who took a skier, while Marcus Stoinis pulled a back-of-a-length ball from Jason Holder to Nicholas Pooran at short midwicket.
Smith and Alex Carey were understandably watchful when they came together at 79 for five, the latter taking 15 balls to get off the mark.
Smith was fortunate on 26 when Cottrell slipped running in to take a catch from long leg but as the partnership started to flourish, Carey perished for 45 after aiming an airy waft at Russell to be caught behind.
Russell, who was included despite doubts about his left knee, limped off the field in clear distress after completing his eighth over.
Coulter-Nile struggled underneath the short ball on occasion but gradually grew in confidence as Smith moved to his half-century after 77 balls.
Coulter-Nile followed Smith to his half-century in far more belligerent fashion, reaching the milestone for the first time in international cricket off 41 balls.
He celebrated by thumping Carlos Brathwaite down the ground for six off the very next ball before being dropped on 61 in the deep by Shimron Hetmyer.
Smith was not so fortunate after Cottrell pulled off an incredible catch running along the deep backward square-leg boundary, ending a partnership of 102 off only 89 balls.
Cottrell plucked the ball out of the air with his left hand, threw it up and then completed the catch after his momentum had briefly taken him over the boundary rope.
Coulter-Nile continued to bludgeon a fatiguing Windies pace attack but his innings, which included eight fours and four sixes, was ended when he picked out Holder in the deep off Brathwaite, who took the final two wickets.
Australia were therefore all out after 49 overs but posted a competitive total, helped in part by 24 wides from the Windies bowlers.