Competing in the second group with eight other athletes, Vien was left behind in the first 100 m and finished last after taking more than two minutes to reach the finish line. Overall, she was 26th of 29 swimmers. Only the top eight can advance to the final.
The top three athletes of the group were American Kate Ledecky with a time of 1 minute and 55.28 seconds, Canada's Penny Oleksiak (1:55.29 seconds) and Australia's Madison Wilson (1:55.87 seconds).
Two minutes and 5.30 seconds is Vien's worst result in the 200m freestyle race. The best result she achieved in this category is 1:58.82 seconds in 2016. At the 2019 Asian Swimming Championship, she won the bronze medal in this category after finishing her part in 1:59.31 seconds.
Vien has another chance in the women's 800 m freestyle, which will take place on Thursday.