[7] At the 2021 Wimbledon Championships – Girls' singles, Xu lost in three sets in the first round to fourth seed Polina Kudermetova.

[12] In April 2024, Xu and Mika Stojsavljevic paired up to win 6-2, 1-6, 12-10 over Flora Johnson & Allegra Korpanec Davies in the girls' doubles at the U18 Junior Nationals Championship.

[15] Playing alongside Stojsavljevic, she reached the final of the girls' doubles at the 2024 Wimbledon Championships, after a win over top seeds and defending champions, Alena Kovačková and Laura Samson, in the quarterfinals and a straight-sets win over Julia Stusek and Julie Pastioka in the semifinals.

[16][17] In the final, they lost on a championship tiebreak to Tyra Caterina Grant and Iva Jovic of the United States.

[19] Partnering with Amelia Rajecki, Xu won the doubles title at the ITF W100 Shrewsbury in October 2024, defeating fellow Britons Hannah Klugman and Ranah Stoiber in the final.