Jordan leads England rally against Sri Lanka
Englands Gary Ballance plays a shot during play in the first ODI match between England and Sri Lanka at The Oval in London on May 22, 2014 - by Ian Kington
The tourists were left needing a Duckworth/Lewis adjusted target of 259 to go 1-0 up in this five-match series after rain had reduced the opening encounter to 29 overs per side.
England were in trouble at 152 for five when off-spinner Sachithra Senanayake, who led Sri Lanka's attack with three for 30, took two wickets for three runs in seven balls to remove Gary Ballance (64) and Ravi Bopara.
But England struck 93 off the last seven overs, with Chris Jordan - whose unbeaten 38 came off just 13 balls -- ending the innings with a straight six off Lasith Malinga.
'Slingshot' seamer Malinga, so often a threat with the white ball, was the most expensive member of the attack, his eight wicketless overs costing 71 runs.
Earlier, Sri Lanka captain Angelo Mathews won the toss and elected to field first in overcast conditions.
England skipper Alastair Cook was caught behind off Nuwan Kulasekara for 11 but fellow opener Ian Bell batted beautifully in making a near run-a-ball fifty that included a straight six off Thisara Perera.
But Bell was out for exactly 50 in the 21st over when he flicked Mathews straight to Malinga at short fine leg.
Bell's exit was the cue for the umpires to take the players off the field as a thunderstorm that delayed play for two-and-a-half hours lashed down upon the ground.
Shortly after the resumption, Eoin Morgan was lbw to Senanayake, who then removed Ballance for an impressive 72-ball knock in his first England innings at number three.
Senanayake also had Ravi Bopara lbw on the sweep before Root, Jos Buttler (26 not out) and Jordan bolstered the total.