Sri Lanka won the toss and invited Pakistan to bat first.
Pakistan were dismissed after scoring 212 runs on the board in 48.4 overs. Hasan Mohsin scored 86 runs from 86 balls with the help of eight fours and a six.
Salman Fayyaz scored 33 runs from 49 balls while Mohammad Umar 26 runs from 54 balls.
Thilan Nimesh, Wanidu de Silva and Damitha Silva took three wickets for Sri Lanka.
In reply, Sri Lanka fell 23 runs short from victory as they were back in the pavilion after scoring 189 runs in 46.4 overs.
Kamindu Mendis scored 68 runs from 104 balls while Vishad Randika contributed 46 runs of 71 balls.
Shadab Khan took three wickets for the green shirts while Hasan Mohsin, Sameen Gul and Ahmad Shafiq each got two wickets as well.
Mohsin was named Player of the match.