Sri Lanka U-19s307 (Vithanage 80, Daniel 52) and 94 for 3 (Asalanka 40*) beat England U-19s 208 (Holden 111*, Kumara 7-82) and 192 (Kumara 4-52) by seven wickets
England Under-19s suffered their first home defeat for six years in a four-day match as an outstanding bowling performance by Lahiru Kumara fired Sri Lanka to a seven-wicket victory in Northampton.
Kumara, a well-built seamer from Kandy, claimed four more wickets as England could only manage 192 in their second innings. That completed match figures of 11 for 134, and left Sri Lanka needing only 94 for victory.
They knocked them off for the loss of three wickets, two of them to Warwickshire seamer George Panayi, meaning they win the two-match series 1-0 after England enjoyed the better of a rain-affected draw in Cambridge last week.
England's last home four-day defeat had also come against Sri Lanka in Northampton in 2010, when a team including Joe Root and Jake Ball were beaten by 199 runs.
They made a promising start on the third morning after resuming their second innings on 24 for 1, with Olly Westbury and George Hankins surviving a searching examination from Kumara and Jehan Daniel who both generated consistent and considerable in-swing to the right-handers.
It was the introduction of spin which broke the stand as Hankins was lbw trying to sweep the slow-left-arm of Praveen Jayawickrama, ending a restrained innings of 20 from 70 balls from the Gloucestershire batsman.
The next blow to England was self-inflicted as Westbury, the Worcestershire opener who made 196 in Cambridge and had compiled a patient 41 from 109 balls, was run out by a call for a quick single from George Bartlett.
Next ball, Westbury's Worcestershire team-mate Josh Dell became the first of two England batsmen to complete a pair, although he was unlucky to be brilliantly caught at silly point as he pushed forward to Jayawickrama.
That left England on 89 for 4, still 10 runs behind. Bartlett, the Somerset batsman who also scored a century at Fenner's, did his best to repair the damage by making 26, before edging a superb delivery from Kumara to third slip soon after lunch.
Hampshire's Josh McCoy completed England's second pair when he was bowled by Kumara, but Surrey's wicketkeeper Ollie Pope made a promising 23 from 31 balls until he was also trapped lbw by Jayawickrama.
The Essex seamer Aaron Beard then joined Yorkshire's Ed Barnes to put on 48 for the eighth wicket, the second highest stand of the innings. But Beard chipped a full toss from Sri Lanka's captain Charith Asalanka to mid-off, and George Panayi edged the next ball to slip.
Amar Virdi was the last man out, leaving Barnes unbeaten on 18. The Yorkshireman also claimed a wicket in Sri Lanka's second innings, as Dilan Jayalath holed out to Bartlett on the square leg boundary, and Panayi briefly raised England's hopes when he trapped Avishka Fernando lbw with his fourth ball.
But Sri Lanka's captain Charith Asalanka ensured there were no nerves in such a small chase by cracking 40 from 18 balls including two sixes, one of which soared over the signal box at Wantage Road and into the gardens of Clarke Road.
England have the chance to hit back in a three-match Royal London One-Day Series which starts at Wormsley next Wednesday, and ends with a day-night game at the Spitfire Ground, St Lawrence on Tuesday week which will be televised live by Sky Sports.