West Indies bowled a disciplined line and length to dismiss Pakistan for 232 in the second one-day international at Sheikh Zayed Stadium on Friday.
Fast bowler Jerome Taylor overcame a final over glitch in the previous match to take 3-38 and was ably supported by Daren Powell 3-50 as they never allowed the Pakistani batsmen liberty on a docile pitch.
Pakistan, who had collapsed to seven for two in the third over, were indebted to Misbahul Haq (52), Kamran Akmal (45) and Younus Khan (34) but none could play long enough for a big total after Pakistan won the toss and batted.
Younus and Haq staged a little recovery through a 51-run third wicket stand before both fell to injudicious shots. Younus played across to Daren Powell, while Haq miscued a drive off spinner Nikita Miller and was caught in the deep.
Younus hit five boundaries while Haq managed just one during his slow 86-ball knock.
Pakistan were further jolted when captain Shoaib Malik was run out for ten.
It was left to Akmal, who hit Taylor for two sixes in the 50th over to give Pakistan an unexpected win in the first match on Wednesday, and Shahid Afridi (28) to give some respectability to the innings.
They shared a rapid 52-run stand and threatened for more but West Indies hit back, dismissing both in the space of just two runs.
Sohail Tanveer (26) used the long handle effectively, hitting Taylor for three boundaries in the 48th over before he was run out.
Pakistan leads the three-match series 1-0.