Marin, seeded fourth, made light work of Sindhu as she swept aside her Indian nemesis with a comfortable 21-11, 21-15 win at the Indoor Stadium.

The 23-year-old needed just 35 minutes to secure her spot in the last four, where she will go up against second seed Sung Ji-hyun of South Korea.

Sung, bronze medallist at the 2015 World Championships, dispatched Chinese sixth seed Sun Yu 21-13, 21-16 to progress to the semi-finals.

American player Beiwen Zhang caused an upset as she knocked out Akane Yamaguchi, Japan's third seed, thanks to a battling 21-15, 21-23, 21-19 victory.

Her reward is a meeting with top seed Tai Tzu Ying of Chinese Taipei, who beat Japan's Sayaka Sato 21-14, 21-19.

In the men's singles draw, China's fifth seed Shi Yuqi, the only seeded player left in the competition, crashed out as he was beaten by India's Srikanth Kidambi.

The Indian star proved too strong for his opponent, progressing by virtue of a 21-14, 21-16 success.

Kidambi will next face Anthony Sinisuka Ginting of Indonesia, who ousted Wong Wing Ki Vincent of Hong Kong 21-19, 21-14.

Kidambi's team-mate Sai Praneeth Bhamidipati also prolonged his stay at the event in Singapore as he fought back from a game down to dispatch eighth seed Tanongsak Saensomboonsuk of Thailand.

Bhamidipati saved his best form for the quarter-finals of the competition as he claimed a hard-fought 15-21, 21-14, 21-19 win.

South Korea's Lee Dong-keun will be his opponent in tomorrow's semi-final after he beat Indonesia's Jonathan Christie 21-18, 21-16.