The 11-4, 6-11, 11-3, 11-5, 11-3 win at ÖVB Arena avenged Xu's shock loss to Gauzy in the third round of this year's ITTF World Championships in Hungary's capital Budapest.

Next up for him is South Korea's Lee Sangsu, who defeated Greece's Panagiotis Gionis 2-11, 12-14, 11-9, 9-11, 11-6, 11-6, 13-11.

Joining Xu in the round of 16 is second-seeded compatriot Fan Zhendong after he overcame Nigeria's Quadri Aruna 8-11, 11-7, 11-9, 14-12, 11-7.

The most notable casualty from the men's singles was eighth-seeded Taiwanese Lin Yun-Ju, losing 8-11, 11-4, 11-8, 6-11, 8-11, 11-8, 7-11 to South Korea's Jeoung Youngsik.

In the women's singles event, the highest-seeded player to suffer elimination was sixth-ranked Miu Hirano of Japan.

The 2016 ITTF World Cup winner lost 11-7, 8-11, 4-11, 3-11, 7-11 to China's Wang Yidi.

Another eye-catching result was world number 181 Olga Vorobeva's victory at the expense of 13th-seeded Romanian Bernadette Szőcs.

The Russian qualifier prevailed 11-9, 11-9, 11-9, 4-11, 13-11 in one of the biggest upsets of the tournament so far.

Top seed Chen Meng of China beat Sweden's Matilda Ekholm 11-6, 11-4, 11-3, 11-6, while second-seeded compatriot Wang Manyu defeated fellow Chinese Liu Fei 11-7, 11-6, 11-8, 11-2.

Chen is looking to equal the record for ITTF World Tour titles in a calendar year.

The world number one has four triumphs to her name so far this season and will equal the five claimed by legendary compatriot Zhang Yining, who achieved the feat in 2003, if she emerges victorious in Bremen.