Hambantota (AP): Sri Lanka has several headaches ahead of its World Cup qualifiers in two weeks' time after suffering a heavy six-wickets defeat against Afghanistan on Friday.

Set a target of 269, Afghanistan got there with 19 deliveries to spare to take the opener of the three-match one-day international series.

Ibrahim Zadran was the hero for the visitors, top scoring with 98 runs. The opening batter took the Sri Lankan quicks to task during the Power Play as he raced to his half-century in just 35 balls.

Zadran, a 21-year-old right-handed batter, settled down after the field restrictions as he added 146 runs with Rahmat Shah for the second wicket as the Afghans proved Sri Lanka's total of 268 was way below par.

Kasun Rajitha broke the stand when he had Zadran caught at deep mid-wicket, just two runs short of his fourth ODI hundred.

Zadran's 98 runs came off 98 balls with 11 hits to the ropes and two over it.

Sri Lanka also dismissed Rahmat Shah for 55 when Matheesha Pathirana claimed his first ODI wicket. But Hashmathullah Shahidi's 38 sealed the game for his side.

The Afghan captain shared 42 runs for the fourth wicket with Mohammad Nabi, who remained 27 not out.

Sri Lanka brought in the experienced Dimuth Karunaratne and Angelo Mathews to the ODI squad to address the team's batting woes.

But it was back to square one as they slumped to 84-4 with Mathews (12) and Karunaratne (4) not able to make big contributions.

Charith Asalanka held the Sri Lankan innings together with his seventh half-century and went on to score 91 off 95 balls with 12 fours. He was well backed up by Dhananjaya de Silva (51) as they shared a 99-run partnership for the fifth wicket. But Sri Lanka needed much more than that.

Asalanka's knock was some consolation for the Sri Lankans, but the former world champions needed the senior players to put their hands up as there were too many soft dismissals.

Afghanistan, which has already qualified for the World Cup in India later this year, was without star bowler Rashid Khan, who sat out with a lower back strain. But their bowlers responded well keeping Sri Lanka to a below-par total cutting down the work of the batters.