A Kumar Sangakkara century led Sri Lanka to a 90-run victory over England in the sixth one-day international, a win that sealed the series 4-2 on a miserable day for Alastair Cook.

Cook dropped a simple catch when Sangakkara was on 41, the left-hander going on to 112 in Sri Lanka's 292-7.

The captain was then lbw for one in the first over of England's reply.

The tourists slumped to 84-5 and, despite 55 from Joe Root, were bowled out for 202 with 8.3 overs unused.

For all the promise of the win in the fifth ODI, England were ragged in the field, saw their bowlers struggle late in the Sri Lanka innings and their batsmen fail when faced with a big chase on a Pallekele pitch offering turn and some uneven bounce.

In the context of their World Cup  preparations, they can take comfort from the fact that conditions in Australia and New Zealand will be vastly different to those in Sri Lanka and their bowling will be boosted by the returns of James Anderson and Stuart Broad.

However, the form of Cook remains a concern.

If dropping Sangakkara - a knee-high chance at mid-off - was an aberration, his meek surrender with the bat was familiar.

Missing a straight ball from off-spinner Sachithra Senanayake, Cook was leg before for the third time in the series. The skipper has now scored 499 runs at an average of 24.95 in his last 21 ODIs, during which time England have won only eight matches and suffered four series defeats.

His dismissal set the tone for the early part England chase as James Taylor ran past one to be bowled by Senanayake and Moeen Ali feathered a beautiful Tillakaratne Dilshan off-break.

And when Ravi Bopara and Eoin Morgan fell to successive Suranga Lakmal deliveries, England were in danger of imploding.

The busy Root at least provided a glimmer of hope, but when the Yorkshire batsman was bowled attempting to scoop Lakmal the game was up.

That Sri Lanka had posted a total so far beyond the reach of England was down to the imperious Sangakkara, who made a 20th century in the last ODI appearance on his home ground.

The wicketkeeper accumulated singles down the ground, showed deft footwork to loft over mid-wicket and power to take a six each over long leg and long-on.

His fifth successive score of 50 or more is made all the more impressive by the fact he broke a rib in practice before the series began.

He was supported by Dilshan, who compiled a watchful 68, a second-wicket stand of 153 providing the platform from which Sri Lanka added 130 in the final 15 overs.

James Tredwell gave England control with 1-37 from 10 overs, but their pace trio came in for late punishment.

Too often dropping short, Chris Woakes and Steven Finn could not replicate an impressive opening burst, while Chris Jordan conceded 68 runs in nine overs. (BBC)