A chanceless unbeaten 134 from Kumar Sangakkara inspired Sri Lanka to a seven-wicket win against an overly cautious England to leave their Champions Trophy group wide open ahead of the final two matches.
A victory would have taken England through to the semi-finals as one of the top two, while defeat would have dumped Sri Lanka out. But all is still left to play for, with New Zealand leading Group A on three points.
England, who face New Zealand in Cardiff tomorrow, and Sri Lanka are on two points, with Australia on one ahead of their meeting with Angelo Mathews' side at the Oval on Monday.
"I was pretty happy with the way I went about it," Sangakkara said at the post-match presentation. "It was tough on the bowlers, but both sides batted well. We've got to win the next one, hopefully our run rate has done some good today and we'll have to prepare well for the Aussies."
The No3 batsman paced himself perfectly in Sri Lanka's 297 for three from 47.1 overs to notch his 15th one-day international ton under overcast skies.
England's batsmen earlier took their time in trademark style before some last-over fireworks by Ravi Bopara helped them make 293 for seven amid woeful Sri Lankan fielding.
The tournament hosts have been criticised by commentators for their recent ponderous batting in the 50-over format, yet still beat Australia by 48 runs in their opening game. This time, they managed only 38 runs in the first 10-over powerplay, when sides such as India - who have already reached the last four from Group B - have notched in excess of 60.
England are confident of defending totals around 270, despite 325 now being very possible in the explosive modern one-day game, and it looked like they would make only a decent score before Bopara (33 not out) blasted 28 off Shaminda Eranga's final over. His cameo included the only three sixes of the innings, but proved not to be enough.
"I thought 300 was about par. I couldn't get my innings away. If I had done, we might have got to 320," said England captain Alastair Cook, who also felt his bowlers' rhythm and hopes of reverse swing were upset by a ball change. "Sometimes you come up short, but we'll have a look at it and come back on Sunday."