Joe Root's century was in vain as England's bid to reach the World Cup quarter-finals suffered another setback with a nine-wicket defeat to Sri Lanka in Wellington.

Root became England’s youngest centurion at a World Cup, at the age of 24, as his career-best 121 from 108 balls helped his side post a formidable 309 for six.

But Sri Lanka comfortably reeled in a record chase at the Wellington Regional Stadium with 16 balls to spare, thanks to twin tons from Lahiru Thirimanne and Kumar Sangakkara, to inflict yet more pain for England at the venue.

England suffered one of their worst-ever World Cup defeats at the ground nine days ago, when they were left humbled by New Zealand, and this latest reverse means they now have no room for error if they are to reach the knockout phase.

England must win their final two group games against lower-ranked Bangladesh and Afghanistan in the next fortnight or face the unthinkable prospect of going home prematurely.

Defeat was England’s third to higher-ranked opposition at the tournament with their only success the 119-run win over Scotland in Christchurch last Monday.

Sri Lanka made England pay for the slightest of mid-innings stutters — and a failure to make any impression with the ball — in what was otherwise their best batting performance of the tournament so far.

England got off to a rollicking start, chiefly due to Ian Bell, as they crunched eight fours in the first five overs. But they managed just eight more in the next 25 overs.

While that set the platform for some enterprising late hitting — 148 runs were taken from the final 15 overs as Root unfurled his full range of shots — Sri Lanka were able to keep their foot on the accelerator throughout and there was always a sense of inevitability about their pursuit despite its size.

England were also left to rue dropping Thirimanne when he was on just three. Root was the culprit after he had himself profited on a rare Mahela Jayawardene drop at slip when he was on two.

Root's grassed chance came when Thirimanne edged Stuart Broad between first slip and wicketkeeper.

It immediately appeared it would be costly as Thirimanne launched into some powerful cover drives while Tillakaratne Dilshan swatted Broad over the square-leg fence twice in the same over.

The Sri Lanka openers combined in a century stand in as many balls before Dilshan squeezed Moeen Ali to Eoin Morgan at midwicket.

It was England’s only success with the ball. A punishing unbroken 212-run stand followed between Thirimanne and Sangakkara, who typically exuded grace and calm to a chase that comfortably bettered the 254 for four South Africa managed against New Zealand in 2012 to previously set the venue record.

The 25-year-old Thirimanne showed signs of nerves as he closed in on three figures -which coincidentally made him Sri Lanka’s youngest World Cup centurion - and was given a second life on 98 when Moeen Ali dived over a miscued drive at point.

He eventually got there from his 117th ball, celebrating with a fist pump, before Sangakkara increased his tempo and followed him to a century from 70 deliveries.

It was the 37-year-old’s second century in as many games, after he and Dilshan hit twin tons in Thursday’s win over Bangladesh in Melbourne, and his 23rd in one-day internationals.

It was also enough to again sap English confidence inside the Wellington Regional Stadium, although at least this time they could draw some comfort from a strong batting performance.

Root reached his fourth ODI century from exactly 100 balls, when he cut Angelo Mathews to the point rope, to displace David Gower as England's youngest World Cup centurion after he managed the feat when he was almost two years older at the 1983 tournament.

Root initially had to restore some calm to England’s batting after Bell’s early aggression gave well to a slow spell during which Gary Ballance’s run of outs continued.

Ballance was on six when he meekly bunted a return catch to Dilshan, whose introduction had set the shackles on in the middle overs, while Bell had slowed to 49 from 54 balls by the time he inside edged Suranga Lakmal onto his stumps.

Root therefore set about rebuilding alongside Morgan and they sedately pieced together a 60-run stand. They ran the majority of those too as the boundaries dried up while the skipper mulled over a 47-ball 27 until he cut straight to gully.

Morgan's exit came in the over before the batting powerplay, but Root pressed on as he and James Taylor embarked on a 98-run stand and displayed the type of hitting to prove England can match the late-innings muscle that has been a feature of this World Cup.

Root was eventually trapped lbw by Rangana Herath and Jos Buttler took charge of the hitting — after being hit in the helmet by Lasith Malinga first ball — as he crashed 39 from 19 balls.