Staying at -70 kg/154 lb, he then won the Chinese National Sanshou club Championships in 2005 and 2006, and affirmed himself as the country's top middleweight by winning a tournament held by Heroes of Legends in January 2007.
[2] In September 2007, he won the IFB International Sanda Tournament in Guangzhou, China, defeating Muay Thai stylist Akarn Sannaha by decision in the final.
A month later on October 13, 2007, Xu beat Joey Pagliuso by unanimous decision in Shenzhen, China, using his height and reach advantage to outpoint the American.
[3] Xu won a second Legend of Heroes tournament in December 2008 before losing a unanimous decision to Vuyisile Colossa in the same promotion in Beijing, China on January 18, 2009.
Although a heavy underdog, he scored an upset win by knocking Nagashima down with a left hook inside the opening thirty seconds of the fight before finishing him with the same technique soon after.
[11][12][13] He fought and beat another Thai in his next outing, outpointing Malaipet Sasiprapa at Legends of Heroes: Muaythai vs. Kung Fu at the Arena of Stars in Pahang, Malaysia on October 9, 2010.
[20][21] He put a halt to his three-fight losing streak five months later when he knocked out Adil Abbas at a Legends of Heroes event in Nanchang, China before returning to Europe to compete for the Fight Code promotion and entered into the organization's 2011 Dragons Series -70 kg/154 lb tournament at the quarter-finals stage when he took the place of Dzhabar Askerov who withdrew due to scheduling conflicts.
The fight got off to a rather lackluster start and had the crowd booing at one point in the first round before Xu fell victim to Kido's patented spinning backfist late in the third.
A month later, he stepped in on short notice to replace Yodsanklai Fairtex against Giorgio Petrosyan, with Hero Legends making the fight a title bout.