Despite a roller-coaster 2019, the Chinese Taipei star has still made the semi-finals of every tournament she's entered since crashing out of the World Championships in the last eight in August.
But with the season-ending BWF World Tour Finals upon us, and Tokyo 2020 just months away, we ask, who exactly is Tai Tzu-ying and what makes her tick?
Who is Tai Tzu-ying?
The 25-year-old Tai was born in Kaohsiung, a city in the southern region of the island of Taiwan, where she still resides.
Influenced by her father, Tai picked up badminton in primary school, becoming a top-group player nationally by the age of 12. The Badminton World Federation's archives contain international results for Tai as early as 2007, when she was just 13.
She made her BWF Grand Prix debut two years later in 2009 on home soil at the Chinese Taipei Grand Prix Gold before going on to reach the final of the Vietnam Open; she also played the final of the Singapore Open Super Series in 2010 on her 16th birthday.
"It was my first Super Series final and it was my birthday. The audience collectively gave me their well wishes when I entered the court. That is the most memorable experience I have in the sport so far," she recounted.
But it wasn't until 2011 when the then-17-year-old made her first breakthrough, winning the US Open Grand Prix Gold championship for her first international title, something the shuttler ranks as her most memorable sporting achievement.
The right-hander was named to Chinese Taipei's Olympic team for London 2012. The 18-year-old was the 10th seed and came through her preliminary group with two straight-games wins, but fell to eventual champion Li Xuerui of China in the round of 16.
But she quickly rebounded from disappointment in the British capital, winning the Japan Open Super Series title that September to become the youngest-ever winner of a Super Series tournament (a record since surpassed twice).
In 2014, she became the first Chinese Taipei athlete to win the season-ending Finals championship, a feat she repeated with her victories at the All-England Open (2017), Asia Championships (2017), and Asian Games (2018).
Tai Tzu-ying as world number one
The Kaohsiung shuttler first reached the peak of the world rankings on 1 December 2016, and wasn't budged off the top until the week of 18 April 2018, for a reign of 72 weeks as world number one.
However, a change to the Badminton World Federation's competition schedule and rankings system that year saw Tai overtaken briefly, before she returned to the summit on 3 May following victory in the Asia Championships for a second consecutive year. This time, she led the world rankings until 29 July 2019, for a total of 137 weeks in her two spells as women's singles number one, surpassing the previous record of 124 weeks set by Li, the Chinese player who defeated her at London 2012.
Since then, Tai has been back at the top twice more, and is currently (9 December 2019) still the world number one.
World Championships misses
Despite her successes, Tai is still missing a World Championships medal alongside her lack of metal from the Olympic Games.
In seven appearances at the two global events, she has never made it out of the quarter-finals, with two Olympic round of 16 appearances and five World Championships last-eight finishes.
Additionally, Tai was forced to miss the 2017 World Championships, where she would have been top seed, due to a clash with the Universiade being held in Taipei, which the Chinese Taipei Badminton Association instructed her to attend instead. Tai won two gold medals at that Universiade.
In April 2017, she set her fastest smash speed of 366 kilometres per hour at the Malaysia Open.
The Olympic Channel recently posed the question: Is It Possible for a badminton shuttlecock to travel faster than 500 km/h?