West Indian captain Jason Holder won the toss and decided to bowl first in the first day-night international against Pakistan in Sharjah on Friday.
The twice world champions gave a one-day debut to opener Kraigg Brathwaite, who has played 31 Tests without ever playing a 50-over international.
Pakistan made one change from the side which beat England in their fifth one-day at Cardiff earlier this month, bringing in paceman Wahab Riaz for Umar Gul who was not selected for this series.
The second match will also be played in Sharjah on Sunday while the final match is in Abu Dhabi on October 5.
Pakistan: Azhar Ali (capt), Sharjeel Khan, Babar Azam, Shoaib Malik, Sarfraz Ahmed, Mohammad Rizwan, Mohammad Nawaz, Imad Wasim, Mohammad Amir, Wahab Riaz, Hasan Ali
West Indies: Jason Holder (capt), Sulieman Benn, Carlos Brathwaite, Kraigg Brathwaite, Darren Bravo, Johnson Charles, Shannon Gabriel, Sunil Narine, Kieron Pollard, Denesh Ramdin, Marlon Samuels
Umpires: Ruchira Palliyaguruge (SRI) and Ahsan Raza (PAK)
Tv umpire: Sundaram Ravi (IND)
Match referee: Andy Pycroft (ZIM)