Sindhu, seeded third, tried everything at her disposal but couldn’t find a way to get past the world number four An Seyoung, who gave ample display of her athleticism and precision, leaving the Indian to do the catch-up job from the start.
The second seeded Korean rode on her superb retrieving skills to gallop to a 6-1 lead early on.
Next she dived twice in quick succession on both flanks to blunt Sindhu’s attack and sealed it with a delightful drop.
Two powerful returns took Sindhu to 4-7 but An Seyoung came up with two precise returns, a body blow and then produced another over-the-head return to gain a healthy 11-6 lead at the break.
Sindhu tried to step up the pace but An Seyoung displayed a wide array of shots to always stay a step ahead. The Indian got a few points with her smashes but she couldn’t put pressure on the Korean.
An Seyoung disposed off two weak lifts from Sindhu and then grabbed eight game points, two of which were saved by the Indian before the Korean unleashed a lightening straight smash to seal it comfortably.
Sindhu was off to a good 3-0 start after the change of ends but An Seyoung soon surged ahead to 5-3.
The Indian grabbed two quick points before the match became a tight battle with Sindhu’s precise forecourt return being matched by the booming smashes from the Korean.
A long shot was followed by a net winner from Sindhu to keep the scores tied at 9-9 but the Korean was relentless in her retrievals and soon moved to a two-point advantage when Sindhu shot one to the net.
Sindhu kept breathing down the neck of her opponent at 12-14, with the Korean going long and to the net.
A service error from An Seyoung kept it 14-16 before the Korean produced a cross court return and, with Sindhu also miscuing a couple of shots, it was 18-14 advantage for the local hope.
Sindhu reeled off three points on the trot to keep the match alive but An Seyoung sent one away from the backhand of the Indian, who went to net next to gift three match points to the Korean.
An Seyoung unleashed another smash to seal the match and go down on her knees in joy.
In the men’s singles, Srikanth and Christie entered the contest after winning four matches each in their eight career meetings, with the Indian losing in the semifinals at Swiss Open last month.
On Saturday, the Indonesian was once again more alert and showed better control in the rallies to outwit the Indian.
Srikanth kept things tight in the opening game, managing a 9-7 lead before ensuring a three-point lead at the break.
Christie tried to add more pace in the rallies and drew level at 13-13 after Srikanth went to the net.
The duo moved to 17-17 before a power-packed smash and a perfect return on his opponent’s forehand gave the Indonesian two game points.
The Indian saved one before parring one wide to concede the opening game.
Christie made a bright start with a 3-0 lead and maintained it at the break, with Srikanth lacking consistency with his finishing.
With the Indonesian committing unforced errors, Srikanth managed to make it 11-12 before grabbing a slender 14-13 lead. But Christie responded well, grabbing six points to reach 19-14.
The Indonesian held five match points, while Srikanth saved one before an alert Christie produced another quick return to serve to make his second successive final of a BWF World Tour event.