Sunil Narine claimed figures of 4-26 as the hosts successfully defended 232-8 to atone for Sunday's 126-run defeat to the men in green.
Narine had earlier finished on one not out alongside Dwayne Bravo, who contributed an unbeaten 43 with the bat to help his side post a decent total following a nightmare start.
After losing the toss, the Windies lost the wicket of danger man Chris Gayle inside the opening over.
Fellow opener Johnson Charles made up for Gayle's shortcomings with the bat, smashing three fours and one six to push his side to 50-1 before rain stopped play in the 11th over.
The 40-minute rain break seemed to stagnate the West Indian innings and, after losing Charles (31) to an Akmal stumping off the bowling of Shahid Afridi, it took the hosts until the end of the 27th over to reach 100-2.
Lendl Simmons (10) became Afridi's second victim, as Akmal claimed a high catch.
Pakistan's reply got off to a slow start, but the Windies had to wait until the 11th over for their first breakthrough.
After bowling four of his first five overs as maidens, Roach was finally rewarded with a wicket, as Ahmed Shehzad, who made 19 off 33, edged to Charles, leaving the chasers on 37-1.
Mohammad Hafeez (20) was next to go, skying a tempting Narine delivery to Simmons in the deep.
Misbah-ul-Haq's (17) middle stump was then uprooted by Sammy, following an poorshot by the Pakistan skipper.
Nasir Jamshed (54) rode his luck en route to recording his eighth ODI 50.
The left-hander survived four dropped catches and a missed stumping, before Pollard finally worked his magic in the powerplay to manufacture another catching opportunity, which Roach took well.
Narine then took centre stage to dismiss Afridi (5), Wahab Riaz (3) and Ajmal (1) in quick succession, leaving Pakistan reeling on 164-8 with 31 balls remaining.
Dwayne Bravo shook off an injury to have a bowl at the death.
His 11 deliveries went for just nine runs and he claimed the wickets of Akmal (50) and Ali (2) to end the game with 13 balls of the Pakistan innings unused.