Runako Morton and Marlon Samuels made half-centuries as West Indies chased down a target of 233 to win the fourth one-day international by five wickets against Zimbabwe in Bulawayo.
The result gives the tourists an unassailable 3-1 lead in the series ahead of Sunday's final match, also in Bulawayo.
Morton (79) and Samuels (62) shared a 105-run, third-wicket stand to get West Indies' run chase back on course following the early loss of Devon Smith (0) and Brenton Parchment (25).
And although both fell short of the winning line, stand-in captain Dwayne Bravo finished the job with an unbeaten run-a-ball 41.
Earlier, Bravo had opted to field first - a decision that looked questionable when Zimbabwe's opening pair Vusi Sibanda and Hamilton Masakadza shared a partnership of 167.
It was not until the 37th over that West Indies made the first breakthrough when Masakadza was stumped off the bowling of leg-spinner Rawl Lewis (1-38) for 80.
Zimbabwe then lost regular wickets to close at 232-9, Jerome Taylor claiming figures of 5-48.
Sibanda was run out for 96, while Brendan Taylor finished unbeaten on 26.