Sri Lanka's imposing total of 326 for 6 off 50 overs, proved beyond England's reach, and they were dismissed for 185 in the 36th over.
Put into bat by England 'A' captain Nick Knight, Sri Lanka ``A' got off to a great start with openers Chandika Hathurusingha and Avishka Gunawardana sharing a stand of 101 off 18 overs.
Gunawardana struck seven fours in his 52-ball knock of 43. Hathurusinghe made 56 off 74 balls with nine fours before being bowled round his legs by left-arm spinner Ashley Giles who was again the pick of the England 'A' bowlers with 3 for 52 off his 10 overs.
The best part of the batting came in a third wicket partnership of 109 off 84 balls between Russel Arnold and Mahela Jayawardene. The tall left-hander Arnold batting freely struck one six and eight fours for a top score of 87 off 74 balls. Jayawardene rattled off his half-century off 45 balls stroking five fours.
However, the most destructive strokeplay came from Upul Chandana, who slammed an undefeated 34 off only 13 balls hitting three massive sixes and two fours, to enable Sri Lanka go past the 300-run mark. Chandana finished the innings with a six off Mark Ealham, who was the most expensive bowler conceding 74 runs off 10 overs.
England 'A' were put on the defensive when Sri Lanka grabbed three early wickets for 30 runs in eight overs, including that of skipper Nick Knight to the second ball of the innings for a duck, the dangerous Ben Hollioake for 12, and the in-form Darren Maddy for 10. Hollioake and Maddy fell to outstanding catches by Chandika Hathurusinghe at short midwicket and Mahela Jayawardene at square-leg.
Although Andrew Flintoff and Alan Ealham attempted to raise the run rate to the required 6.54 runs per over with an 87-run fourth wicket stand, the writing was on the wall for England once the pair was separated by leg-spinner Upul Chandana.
Flintoff using his height and build to full use punched six fours and two sixes in his 51 scored off 47 balls. Ealham made 48 off 56 balls with two sixes and four fours.
The rest of the batting with the exception of Ashley Giles, who scored 35 off 21 balls, failed to raise the run rate against sharp fielding and accurate bowling and crumbled, with the last four wickets tumbling for eight runs. Hemantha Boteju who removed Maddy and Hollioake came back later to clean up the tail adding the wickets of Giles and Ormond to finish with figures of 4 for 33.