Jan 27 (IANS) Reigning world badminton champion P.V. Sindhu on Wednesday went down fighting to world No.1 Tai Tzu Ying of Chinese Taipei in her first group match of the women's singles of the World Tour Finals. In the men's category, India's former world No.1 Kidambi Srikanth also lost his first match to Denmark's Anders Antonsen. While Sindhu went down 21-19, 12-21, 17-21 in a Group B match that lasted almost an hour, Srikanth lost 21-15, 15-21, 18-21 in 77 minutes in Group B. In the opening game, Tzu Ying started off brilliantly against Sindhu and took a healthy lead at the mid-game break. However, Sindhu staged a brilliant turnaround as she came out with a spirited performance and went on to the clinch the game 21-19 in 20 minutes. In the second game, world No.1 Tzu Ying, however, raced to a 6-0 lead. Sindhu did try to stage a comeback, but her opponent was too good and won the game 21-12 to force the match into the decider. In the third and final game, 2016 Olympic silver medallist Sindhu did put up some fight, but it wasn't enough as Tzu Ying won the game 21-17 to seal the match. Sindhu, 25, will next face Thai Ratchanok Intanon, who defeated her last week in a lop-sided Thailand Open quarter-final clash. Sindhu has to win at least two matches at the round robin stage to make it to the semi-finals. Pornpawee Chochuwong of Thailand is the fourth member of Group B. Eight highest ranked players compete in each of the five events -- men's and women's singles, men's and women's doubles, and mixed doubles - at the World Tour Finals, offering total prize money of $1,500,000. The eight entries are divided into two groups of four. The group matches are played in a round-robin format, with the top two finishers in each group advancing to the semi-finals. Sindhu is the only Indian to win the tournament, achieving that feat in 2018.