In one corner was a highly successful veteran of the pop music industry and in the other, a singer half his age bolstered by millions of enthusiastic, web-savvy young fans.

In this new type of celebrity battle, fan support was more important than concert box-office tallies, music sales, critics' reviews or any of the traditional measurements for music industry success.

The battle was waged by fans of the two singers on the Chinese micro blog Sina Weibo.

The veteran, Jay Chou, 40, from Taiwan, became an overnight sensation after his album Jay was released in 2000. For nearly 20 years, the singer-songwriter has been widely hailed as the king of Asian pop, praised for the originality and diversity of his tracks, numerous music awards and influence on the Chinese-speaking music world.

The upstart, mainland singer Cai Xukun, 21, who came to prominence last year after winning an internet talent show, Idol Producer.

The battleground was Weibo's world of Super Topics, which are like community pages - often created for celebrities, teams or TV shows - where fans can share information.

Weibo ranks these super groups by their popularity, and here, Cai had been dominant for well over a year, taking the No 1 spot on the Weibo top 100 Super Topic list for 64 consecutive weeks.

Despite Chou's success, in recent years, fresher talent has dominated trending topics on social media, and Chou, who married in 2015, now has two children and is not quite as musically active as he once was. Perhaps most telling was that in switched-on China, he doesn't even have a Weibo account of his own.

The contest of the two fan bases began on July 16 with a post on Douban, a Chinese review site, in which an internet user cast doubt on Chou's prowess, citing what was called his mediocre "data performance" on social media.

"I've heard that it's hard to get his concert tickets," the post said. "But I found out that he couldn't even make it into Weibo's top 100 Super Topic list."