Cumbrian Ben Stokes struck the winning runs as England thrashed the West Indies by eight wickets in the Cricket World Cup.

The all-rounder, from Cockermouth, had a relatively quiet match, going for 0-25 from his four overs with the ball, but joined centurion Joe Root (100 not out) at the crease at the Hampshire Bowl to score 10 off six balls and help earn England their third win of the tournament from their four matches.

But the celebratory mood in Southampton was punctured by injury scares for captain Eoin Morgan and opener Jason Roy.

Roy hurt his left hamstring sprinting at cover and Morgan headed straight for the pavilion after a back spasm, with neither man taking their usual places in the batting order.

England will be desperate for positive news from the treatment room but the pair were not missed on the day, a modest chase of 213 proving a walk in the park for Root, who opened for the first time in his international one-day career and scored a century.

Root had already played an unlikely role with the ball, taking two wickets with his occasional off-spin, and the role reversals continued with a Chris Woakes cameo at number three.

Having never batted higher than seven in his previous 91 appearances, the all-rounder was handed an emergency elevation and chipped in with an assured 40 before he was dismissed by Shannon Gabriel.

The game was brilliantly set up by the bowlers, Barbados-born seamer Jofra Archer and Mark Wood delivering with pace and purpose as they shared combined figures of six for 48.

Archer's first appearance against the team he had represented at Under-19 level had been much debated, but he took the moment in his stride as the Windies slid from 144 for three to 212 all out.

All eyes were on the 24-year-old after England opted to bowl first but first blood went to Woakes, scattering Evin Lewis' stumps with a toe-crushing yorker in the third over.

Woakes thought he had a second - the prize scalp of Chris Gayle - but was left aghast as a tough chance popped out of Wood's hands at third man.

Giving Gayle a second chance can be among the costliest mistakes in one-day cricket, and a smooth six down the ground suggested the price tag might be a hefty one. Yet the burly Jamaican never quite made England pay, making 36 before pulling Liam Plunkett to deep midwicket as the Windies set England a target of 213.

Root replaced Roy at the head of England's innings and joined fellow Yorkshireman Bairstow in ramming home the advantage.

They took 62 off the first 10 overs, Bairstow taking care of business as usual and Root piercing the infield with a selection of sweetly-hit drives.

The first breakthrough came with 95 on the board, Bairstow uppercutting Gabriel to third man, leading to the surprise emergence of Woakes at number three.

Any doubts about the wisdom of the promotion were swiftly dispelled, getting off the mark with a punch for four then pulling Gabriel to the ropes. A 104-run stand made the result safe, Woakes falling just before the line but Root safely reaching his 16th one-day ton and third on the World Cup stage.

England have nudged up to second in the table, ahead of Tuesday's inviting game against Afghanistan.