The 2025 Sudirman Cup ended with China beating South Korea 3:1. Story-wise it is nothing remarkable. But from the sports analytics perspective, it reveals much interesting about the nature and patterns of athletic competitions.
First the 2025 Final details:
1. Mixed Doubles: Feng Yanzhe / Huang Dongping (CHN) 2:1 vs Seo Seung-jae / Chae Yu-jung (KOR) 21–16, 17–21, 21–15
2. Women's Singles: An Se-young (KOR) 2:0 vs Wang Zhiyi (CHN) 21–17, 21–16
3. Men's Singles: Shi Yuqi (CHN) 2:0 vs Jeon Hyeok-jin (KOR) 21–5, 21–5
4. Women's Doubles: Liu Shengshu / Tan Ning (CHN) 2:0 vs Baek Ha-na / Lee So-hee (KOR) 21–14, 21–17.
Of the four matches, only the first one was competitive. On paper, the fourth should have been as well, but why not? L/T and B/L are both attacking players. L/T are better at attacking, playing like Men’s Doubles pairs, while B/L have better stamina. Their matchup favors L/T since the matches would have short rallies, with less emphasis on stamina. Still, it could have been 2:1, or a close 2:0, yet the match was more lopsided than what 21–14, 21–17 suggested.
The reason is
what happened in the semifinals a day earlier.
B/L beat the INA WD pair 2:1 in the deciding match to secure a 3:2
victory for South Korea, after which they had less time to recover before the final. (L/T didn’t play in
the semifinal, as China won 3:0 over Japan.)
The situation B/L is in is part bad luck and part their own fault. In the semifinal leading up to the B/L match,
INA MD scored a close 2:1 victory, forcing the WD match. This may be bad luck for South Korea, as the
South Korean MD could have won to end it, but MD competitions are always fierce,
and INA MDs are very strong. But B/L
could still have beaten the INA WD 2:0.
After winning the first set easily, B/L played lazy, allowing INA to
attack, hoping they would make enough mistakes, but they did not. B/L turned around only in the second half of
the third set, more attacking to seal the fate.
Had B/L won by 2:0, they would have had more time to recover, albeit less energy than the completely fresh L/T. This, now leads to interesting and nice comparison with the 2023 and 2017 Sudirman Cup.
In the 2023 Sudirman Cup, China had the toughest road (the May 22, 2023 blog), going through INA, Japan, and South Korea. Hard fought from the Mixed Doubles and on, especially with Shi Yuqi, who played in all three matches. Shi Yuqi beat two strong opponents, Ginting and Naraoka, earlier, but China still sent him against South Korea, a questionable move, since any Chinese MS player would have won the point, while Shi Yuqi was short of breath. It showed later in the match, even though China eventually dodged a bullet (the May 22, 2023 blog).
2025 was opposite. Shi Yuqi still did all the work, but this time was much easier. He beat LJH of Malaysia handily 2:0. LJH was likely tired from his 2:1 win over Naraoka the day before. Shi then beat Naraoka handily 2:0 in the semi. Naraoka didn’t play a day earlier, but his form has dropped in 2025. There is no argument against sending Shi out again in the Final against South Korea this time, since China needed to secure the point in anticipation of losing the WS point, and Shi did his job in a super quick fashion.
In this sense, Shi Yuqi and China are lucky in 2025. South Korea had less time to recover because their semi started later, but of the first three matches in the Final, the stamina issue is immaterial because the players involved either did their semi matches according to plans or didn’t play (Wang Zhiyi). So the only complaint would have been for B/L, yet even there, bad luck was only part of the problem.
But bad luck from a sequence of events was more pronounced and consequential in the 2017 Sudirman Cup, resulting in South Korea beating China 3:2 in the Final. Like South Korea in 2025, China had a later start in semi vs Japan in 2017. Japan was also stronger than South Korea then, so China got the harder draw. Ultimately, Chinese loss to Korea could be traced to the first semifinal match against Japan, when Zheng Siwei/Chen Qingchen lost to Yuta Watanabe/Arisa Higashino 12–21, 21–14, 19–21. This loss necessitated Chen Qingchen to play the 5th, WD match, when she and Jia Yifan defeated Misaki Matsutomo/Ayaka Takahashi 21–12, 21–19. But hours later she and Jia Yifan had to play the WD again in the Final, eventually losing to Chang Ye-na/Lee So-hee 21–19, 21–13. A young Chen Qingchen running out of gas is the reason why she and China lost in the 2017 Final.
So the moral
here is that sports are physical in nature, often times a win and a loss are separated by
the tiniest margin, influenced by pure luck and what happened yesterday. Most casual spectators and even sports fans don’t
recognize that, instead heaping unfair criticisms on their teams and players.
South Korea could argue that Seo SJ played both the Mixed and Men’s Doubles in the 2025 semi and was as tired in the Final as Chen Qingchen in 2017. But because of South Korea’s MS situation and INA’s clever player selection, Seo SJ was bound to play two semifinal matches anyway, and whether he won or lost the second match had no bearing on his physicals in the first match in the Final. In other words, South Korea had it in the plans and must have prepared for it already. But Zheng Siwei/Chen Qingchen losing in the third set by 2 points in 2017 was unexpected and definitely impacted a series of things later. If they had had won 21:19 instead losing 19:21, China would have beaten Japan 3:0, and a fresher Chen Qingchen would likely beat South Korea either in the Mixed Doubles or WD the next day. But looking at the bright side, from 2017 on, Chen Qingchen is focused in WD, and Zheng Siwei got a new partner. And they are both Olympics champions now.
