Hasan Ali, the newly crowned top ODI bowler, took three wickets as Sri Lanka were bowled out for 173.
Imad Wasim took two for 13 in his return to the ODI side.
Lahiru Gamage eliminated the early threat of Imam-ul-Haq for 2.
Lahiru Thirimanne was the sole Sri Lankan batsman to score a half-century.
Usman Khan made his ODI debut and finished with 1 for 38.
Both Babar and Malik scored 69 off 101 and 81 balls respectively.
Mickey Arthur hopes Fakhar Zaman picks up his form and starts to fire at the top of the order.
Shoaib Malik and Babar Azam put on a brilliant unbeaten partnership worth 119 runs to beat Sri Lanka by 7 wickets.