In the final on Sunday, Sindhu will be up against top seed Tai Tzu Ying, who moved past south Korean third seed Sung ji Hyun 21-9, 18-21, 21-7 in 52 minutes.
It was Tai's fourth straight win over Sindhu (including last year's Hong Kong Open final) since she was knocked off by the Indian world No. 3 at the 2016 Olympics in Rio. "Congratulations for the silver!".
But it was not to be as Tai took her third Hong Kong Open title, having also won the tournament in 2014. "The 5'3" Tai Tzu then pulled off variations in pace and angles to stretch the lead to 7-2.
Ying, to her credit, put on a great performance, with shooting the shuttle to 352 kmph at the start of the first game, gaining lead on Sindhu instantly, as she kept missing or lagging behind.
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This year's judges include YouTube star Lele Pons and former judge on "America's Next Top Model" Jay Manuel. Miss South Africa, Demi-Leigh Nel-Peters, won the event and will take over for Iris for the coming year.
It was the second successive week that Ratchanok bowed out in the semi-finals of a BWF Superseries tournament. She drew the Taiwanese shuttler close to the net and then started placing the shuttles in hard positions for her.
In the second game, Sindhu was left to deal with some indecision due to the sidewise drift which gave early advantage to Tai Tzu but the Indian levelled the score at 4-4 with a superb return at her rival's forehand.
Tai held the edge for much of the first game before Sindhu rallied to tie it at 18, only for the Taiwanese to rattle off the final three points. Can Sindhu break the jinx?