China's top paddlers opened Olympic year the hard way by slugging it out at arguably the world's toughest table tennis tournament－The Marvelous 12.

With China still the sport's undisputed powerhouse, last week's domestic trials for March's World Team Table Tennis Championships in South Korea are in many ways considered a bigger test for the nation's elite than major international events.

And the tournament again lived up to that billing as world champions fell prey to their hungry young compatriots in a fiercely contested competition in Shenzhen, Guangdong province.

World No 1 Fan Zhendong stormed to the men's singles title by reeling off four straight victories, most significantly against multiple doubles world champion Xu Xin in the final.

Fan's red-hot form extended his winning streak to 35 matches since his triumph at an International Table Tennis Federation World Tour leg in Germany in October.

The women's event saw former world No 1 Zhu Yuling end an 18-month title drought, which stretched back to the World Tour's South Korea stop in July 2018.

As well as confirming their berths in the squad for the Busan worlds, Fan and Zhu each walked away with winner's checks of 1 million yuan (around $144,000). The total prize pool of 5 million yuan is the sport's biggest purse.

"Even though it's a domestic competition, the atmosphere with live broadcasting in a packed stadium makes it a very different experience," Fan said after being crowned champion at Luohu Sports Center on Saturday.

"This is a tougher challenge than sometimes facing overseas opponents internationally. To pull this off means a good start for me entering the Olympic year and I've gained new confidence preparing for the Games," added Fan, who turns 23 on Jan 22.

Jointly presented by the Chinese Table Tennis Association and Tencent Sports, The Marvelous 12 is designed to provide China's best with a tougher test than they would face overseas, with the tournament assuming extra importance in an Olympic year.

The annual event, promoted and marketed by Tencent Sports since its debut in 2017, attracts huge numbers of online viewers and on-site spectators every year.

In a bid to encourage China's most promising up-and-coming young paddlers, players have to first pass two single elimination rounds before reaching a final round-robin stage.

Reigning Olympic and world singles champion Ma Long fell victim to the next gen when he slumped to a 4-3 second-round loss against the unheralded Zhou Qihao, while on the women's side, Olympic champ Ding Ning also lost in round two, to eventual winner Zhu.

"The domestic competition just pushed us to go harder physically and mentally to become more resilient and consistent in tough matches as every opponent you are facing is of world-champion class," said Fan.

"It's a healthy competition that keeps our level up there for the long term."

The next gen's rise bodes well for China's hopes of sweeping all five gold medals－men's and women's singles, doubles and mixed doubles－in Tokyo this summer.

However, CTTA chairman Liu Guoliang is warning against complacency. The legendary former player and coach stressed that Olympic host Japan's rising young talents, who stunned China's established stars on multiple occasions in 2018, are a force to be reckoned with.

"We still have huge room for improvement in terms of our management system, daily standards and performance during competitions. Also, the skills of our players are still not good enough," Liu said earlier last month after China won four of five gold medals on offer at the World Tour's Grand Finals in Zhengzhou, Henan province.