Seeded third, Saina went down 15-21, 19-21 to her lower-ranked opponent in just 39 minutes.
Before Friday's match, the Indian held a 5-2 edge over the Taipei girl. The last time the two met, it was in the semi-finals of Swiss Open in 2013, and Saina won.
The world No. 4-ranked Saina, who recently won the China Open, looked pretty rusty. She was a pale shadow of herself in the opening game before fighting back in the second. However, failed to take the match into the decider.
Breaking away from 2-2 in the first game, there was no looking back for the Taipei girl. She just kept extending her lead, even as the Hyderabadi played the catch-up game.
Although Saina tried her best, she always trailed the sixth seed.
The Olympic bronze medallist pulled up her socks in the second game and came up with an improved show.
It turned out to be a closely fought affair as the game tilted from one end to another and the two shuttlers were tied 19-19. But the world No. 9 Ying came up with two consecutive winners when it mattered most to seal the issue and make it to the semi-finals.
Image: Saina Nehwal
Photograph: Matt King/Getty Images
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