Shi emerged as champion with one day of racing to go after she opened up an unassailable 22-point gap over second placed compatriot Xiaoqing Yu.

The champion has been head and shoulders above her competitors all week and took a victory and second place before a discarded fifth in the final race of the day.

Yu claimed one victory but could manage only record third and seventh places in the other races of the day which was not enough to take the competition to the final day.

Yu does, however, have silver within touching distance as she leads third and fourth place by 10 points.

In the men's RS:X competition it is tight at the top as three Chinese sailors are within three points of each other in the medal positions.

Currently in front is Chunzhuang Liu on 33, while tied on 36 points, just behind, are Mengfan Gao and Bing Ye in second and third respectively. 

It was another good day in the laser event for Croatia's Tonči Stipanović, the Rio 2016 silver medallist, as a victory and a third place moved him 11 points clear at the top.

Stipanović,'s nearest rival is the 2015 Sailing World Cup winner Lorenzo Brando Chiavarini of Britain, who recorded a second and fourth placed finish which moved him to second on 26 points, behind Stipanovic's 15.

In the chasing pack, the most likely to catch Chiavarini is third placed Pavlos Kontides of Cyprus.

With a fifth and seventh, Kontides finds himself six points behind his British rival on 32.

There was yet another perfect day for China's Dongshuang Zhang, who now has one hand on the gold medal in the laser radial, as she takes a 12-point advantage into the medal race.

With seven wins from eight races, Zhang has looked almost unstoppable on home water.

She sits on seven points at the top and second placed Monika Mikkola of Finland could not cut the deficit, only managing a third and a discarded seventh to finish the day on 19 points.

Chinese duo Hao Lan and Chao Wang remain at the summit of the men's 470 fleet event and take a six-point advantage over second placed compatriots Zangjun Xu and Wei Wang into the medal race.

Lan and Wang have 25 points to Xu and Wang's 31, with the second-placed team going into the medal race level with third place Liangdao Weng and Youjian Wen, also of China.

In the women's 470, China's Mengxi Wei and Yani Xu still hold top spot following a second place and a discarded seventh on day four.

The pair hold top spot with 13 points, while second on the leaderboard, China's Shasha Chen and Haiyan Gao, claimed a victory and a second place to open up a six-point gap on the third placed team of Shengnan Ni and Lizhu Huang, also of China, who have 23 points.

China's Lei Gong has led from start to finish in the Finn event and has a five-point lead over second placed compatriot He Chen.

A victory and a second for Gong, compared to a win and a third for Chen, has opened some breathing space for the leader ahead of the final race of the regatta.

Gong has only finished first or second at this event and if he carries on that run he will definitely leave with the gold medal.

The medal races are due to take place tomorrow when all seven fleets will be decided.