2012 Starting the year as the No. 378 in the world, Duan's ranking would improve significantly to No. 128 by the year's end. Some of the highlights of her 2012 season included winning four ITF titles at the 25k level in Wellington, Changwon, Gimcheon and Goyang. Playing qualifying at the
US Open, Duan had her first experience in a
Grand Slam tournament. She would win her first qualifying round defeating
Réka Luca Jani, but would fall in the next round to
Kirsten Flipkens. She received a wild card to the
Guangzhou International and won her first
WTA Tour main-draw match defeating
Luksika Khumkum in the first round. Duan also achieved her best results in ITF events near the end of 2012, reaching the semifinals of 100k+H Ningbo and the finals of 100k Suzhou, losing both matches to top-100 veteran
Hsieh Su-wei.
2013: Major debut Duan was due to make her major singles debut at
Wimbledon but withdrew to compete in the
National Games of China. She made her major singles debut in the main draw of the
US Open, after winning three qualifying matches. However, she lost to sixth seed
Caroline Wozniacki in the opening round. During the televised commentary of her match against Wozniacki, the commentators compared Duan's game to that of former world No. 1,
Lindsay Davenport. They also began referring to her by the nickname of
Duan-venport (段文波特) on the Chinese internet.
2015: First major singles win At
Wimbledon, as a qualifier, Duan defeated
2014 finalist
Eugenie Bouchard in straight sets in the first round. This was considered one of the biggest upsets of the tournament. In the second round, Duan lost to
Tatjana Maria in a long three-set match.
2016: First WTA Tour title In July, she won her first WTA Tour title at the
Jiangxi International Open, defeating
Vania King in the final.
2017: Elite Trophy doubles title In the first-round match at the
Shenzhen Open, Duan wasted three match points and eventually lost to first seed and world No. 3,
Agnieszka Radwańska. At the
Australian Open, she had her best Grand Slam performance to date by defeating
Rebecca Šramková and
Varvara Lepchenko to reach the third round, where she lost to former world No. 1 and eventual finalist,
Venus Williams, 1–6, 0–6. Duan won her first ever WTA Tour doubles title at the
Elite Trophy with
Han Xinyun.
2018: Second doubles title Duan won her second doubles title at the
Taiwan Open, playing with
Wang Yafan.
2019: French Open finalist, Wuhan doubles title Duan and
Zheng Saisai reached the final of the
French Open, losing to
Tímea Babos and
Kristina Mladenovic. In September, they reached the quarterfinals of the
US Open, however, they were beaten by the eventual champions,
Elise Mertens and
Aryna Sabalenka. The following week, with Zheng unavailable, she partnered with
Veronika Kudermetova for the first time to win the doubles title at the
Wuhan Open, beating Mertens and Sabalenka in the final.
2021: Olympics participation She partnered again Zheng Saisai at the delayed
Tokyo Olympics. They lost in the first round. ==Grand Slam performance timelines==