COPENHAGEN - China extended their dominance in women's doubles as Tian Qing and Zhao Yunlei claimed gold at the World Badminton Championships in Copenhagen on Sunday while South Korea struck gold in the men's doubles. Fifth seeds Tian and Zhao added a world title to their Olympic crown by defeating compatriots Yu Yang and Wang Xiaoli in the final to hand China a 12th straight gold medal in the event.

Tian and Qing, who won Olympic gold at London 2012, secured the first gold medal of these championships with a 21-19, 21-15 victory over their fourth seeded opponents to claim their maiden world title. They also completed their collection of world medals having finished as runners-up in 2011 before claiming bronze a year ago.

Tian and Qing used a sequence of four successive points from 10-8 down to take control of the first game before Zhao capitalised on the couple's third set point when she intercepted a mid-court rally.

Yu, a three-time defending champion, and her partner Wang, gold medallist in 2011 and 2013, were then leading the second set 14-13 before their rivals pocketed seven straight points to move to the cusp of the title with Zhao and Tian then dropping to their knees in celebration as the former found the open court on match point.

The win gave the experienced Zhao a seventh world championship medal after another 2009 silver and 2010 bronze in the same event as well as gold (2011) and bronze (2013) in the mixed doubles.

Meanwhile Ko Sung-hyun and Shin Baek-choel, the 12th seeds in Denmark, beat fellow South Koreans Lee Yong-dae and Yoo Yeon-seong 22-20, 21-23, 21-18 in a pulsating 79-minute encounter to record their first major title together. Ko, a silver medallist with Sunday's opponent Yoo in the 2011 tournament, and Shin had already claimed the scalps of the fourth and fifth seed pairings in Denmark and wrapped up a tense opening set against their second-seeded rivals when their opponents netted a service return.

There was again very little to separate the two teams in the second game and it looked as though Ko and Shin would seal the title as Lee dumped a shot into the net to hand the 12th seeds a match point at 20-19. Lee made amends immediately though as he hammered a winner directly at Shin to prolong the contest with the two-time silver medallist and his partner Yoo eventually forcing a decider. However, Ko and Shin were not to be denied second time round as the former drilled an unreturnable overhead into the ground on the pairing's second match point to seal an incredible triumph.