It turned out to be a good toss to lose for Pakistan, as their seamers, led by Umar Gul, set up a comfortable six-wicket win by keeping Sri Lanka to a paltry 135.
Three rain interruptions in the first innings did little to help Sri Lanka's cause.
They struggled to build momentum and sizeable partnerships, and following a lengthy rain interruption, the overs were culled to 42, leaving very few overs in the end to accelerate.
Pakistan too were tested by a probing opening spell by Sri Lanka's seamers, but they could afford to take their time and grind it out.
Pakistan coasted home to extend their recent domination over Sri Lanka, with their ninth win in 11 games.