Seamer Thisara Perera claimed 4-34 and Tillakartane Dilshan hit an unbeaten 50 as Sri Lanka trounced Pakistan by seven wickets in the final one-dayer on Saturday to clinch the series 2-1.
Dhammika Prasad chipped in with two wickets as the hosts bowled Pakistan out for 102 and then surpassed the Duckworth-Lewis target of 101 in the 19th over of a one-sided game in Dambulla.
An hour-long rain interruption after Pakistan had slumped to 81-8 in the 26th over of the first session forced the umpires to reduce the game to 48-overs-a-side.
Sri Lanka galloped home in style to build on the 2-0 sweep in the preceding Test series and left Pakistan searching for answers ahead of the World Cup less than six months away.
Opener Upul Tharanga and Kumar Sangakkara fell cheaply before Mahela Jayawardene (26) and Dilshan put on a 41-run stand for the third wicket.
Dilshan cut Shahid Afridi to the fence to bring up his half-century and also seal his team's easy win.
Fawad Alam top-scored for Pakistan with an unbeaten 38, but eight batsmen failed to reach double figures as the tourists crumbled in 32.1 overs after electing to bat on the slow wicket.
It was Pakistan's lowest one-day total on Sri Lankan soil, falling below the 116 they made against New Zealand at the same venue in 2003.
Pakistan captain Misbahul Haq said it was not a difficult wicket to bat on.
"There was a bit of tennis-ball bounce, but we should still have scored about 240-250 runs," Misbah said. "We lost too many wickets early and could not get a decent total."
Misbah hoped Pakistan will perform better in their next Test and one-day series against Australia in the United Arab Emirates in October.
Sri Lanka's captain Angelo Mathews said his team showed character to bounce back after losing the first match of the series in Hambantota.
"We had to pull up our socks after that loss and we did that quite well," he said. "We gave Thisara [Perera] more opportunities in the series and he proved himself with both bat and ball."
Sri Lanka next host England for a seven-match one-day series starting in November.
Pakistan never recovered after losing opener Sharjeel Khan in the third over, caught at second slip off Prasad.
Prasad, who replaced the off-form Nuwan Kulasekara, then had the other opener, Ahmed Shehzad, caught at mid-on to make it 14-2.