China's Fu/Zhang win badminton men's doubles in Singapore Open

China's badminton duo Fu Haifeng and Zhang Nan were crowned after a fierce men's doubles matchup with their Japanese counterparts Takeshi Kamura and Keigo Sonoda in Singapore Open on Sunday.

Indonesia's Sony Dwi Kuncoro and Thailand's Ratchanok Intanon won men's and women's singles finale respectively.

Fourth seeds Fu Haifeng and Zhang Nan turned in a rampant performance to win at 21-11, 22-20.

"We encountered some difficulties in the second game, with the Japanese pair competing against us very fiercely, but we finally made it by encouraging each other," Zhang said.

33-year-old Fu said the champion has been his most-wanted one since he finished the Sudirman Cup last year, and success here offered them great courage to prepare for the upcoming Thomas Cup.

As of the Rio Olympics, Fu said it would be his fourth Olympic Games and he "has no burden and only wants to play well in every game".

Ratchanok has completed a historical hat-trick in Superseries, following victories in India Open and Malaysia Open earlier this month.

The Thai shuttler came back from a set down to win defending champion Sun Yu 18-21, 21-11, 21-14, dethroning Carolina Marin as the new world No. 1 in women's singles.

Ratchanok became the first women' s singles shuttler to win three straight titles in a month.

Ratachanok said: "Today I made many mistakes and so did my opponent but I managed to get back into the game earlier than her."

"I just tried to relax. My target was to be world No. 1 and now I'm looking forward to the Olympics where I want to win the gold medal for Thailand," added the 21-year-old.

"She changed some of her tactics during the last two sets and I did not have much to tackle her back. I got more panicky when she started to change her strategies and made a few mistakes," said Sun.

Kuncoro completed what has been a truly remarkable tournament as he won men' s singles title after his triumph over South Korean Son Wan Ho in the final, joining the likes of Boonsak Ponsana and Taufik Hidayat as shuttlers who have won the Singapore Open twice.

Kuncoro, 31, who qualified for the main draw after two wins in the qualifying rounds, was riding on the confidence from usurping two-time Olympic gold medalist Lin Dan just a day earlier as he cruised to a win in his first game 21-16.

But a second game riddled with Kuncoro's errors saw Son take advantage and win 21-13 as the match went to rubber. Then Kuncoro dug deep and showed just why he had deserved a place in the final, storming to a 21-14 win in the tiebreaker.

Kuncoro, who played six matches prior to the final, said: "It' s really unexpected that I won."

"It' s such a big achievement to pass the qualifiers and win this tournament. I just enjoyed today' s game and was able to play well," he said.

In women's doubles, Indonesia pair Nitya Krishinda Maheswari and Greysia Polii were crowned after Japan's Misaki Matsutomo and Ayaka Takahashi withdrew from the final due to a left ankle injury to Matsutomo.

The mixed doubles titleholder were South Korean pair Ko Sung Hyun and Kim Ha Na, who won in straight sets 21-17, 21-14 over China' s Xu Chen and Ma Jin. Endit