A rampant Nepal rewrote the T20 international cricket record books at the Asian Games on Wednesday while China's Zhang Yufei laid down another marker for the Paris Olympics in the swimming pool.

Hosts China lead the medals table with 72 golds, far ahead of South Korea (16) and Japan (13), after adding titles in artistic gymnastics, chess, sailing, shooting, wushu and beach volleyball, AFP reported.

In some of the first action on day four in Hangzhou, Nepal smashed a series of records to open the men's cricket competition in a 273-run thumping of bewildered part-timers Mongolia.

Nepal bludgeoned 314-3 in their 20 overs, beating the previous highest T20 men's international innings of 278-3 by Afghanistan against Ireland in 2019.

Teenager Kushal Malla, batting number three, spearheaded the onslaught by crashing the fastest T20 international century off 34 balls.

Among the other records they racked up, Dipendra Singh Airee hit a scarcely believable eight sixes in an unbeaten 52 off 10 balls.

The powerful 23-year-old raced to his fifty off nine balls, another T20 world record and one that should stand in perpetuity because it is mathematically impossible to reach the landmark any quicker.

Nepal's 26 sixes in the innings was also the best ever.

Mongolia, whose women's team were bowled out for just 15 at the Asian Games last week, were dismissed for only 41 in 13.1 overs.

Much sterner tests await for Nepal, with India and Pakistan both in the draw.

In another gold rush for hosts China, they won the women's and men's street finals in skateboarding thanks to a couple of teenagers.

The 16-year-old Zhang Jie triumphed in the men's and Cui Chenxi, just 13, won the women's.

But China did not have it all their own way as Japan won all three golds on offer on the day on the cycling track ahead of the hosts.

Japan sped to victory in women's and men's team pursuit, and in women's keirin.

Japan's Naoki Kojima said he and his team-mates were celebrating well before they crossed the line in the men's team pursuit.

"In the last three or four laps we knew that we'd win," he said.

"I was behind my teammates and I was supposed to lead the last lap.

"I checked the other riders and I knew we had enough power to win.

"We were actually already celebrating during the last three or four laps."

Zhang fires warning

Seven golds will be won later in the day in swimming, one of the most prestigious events at the Games and boasting some of the best swimmers in the world, AFP reported.

There is added intrigue with the 2024 Paris Olympics coming up fast, less than 10 months away.

The hosts have been particularly impressive, topping the podium in 15 of the 20 races at the halfway mark of the six-day swimming event.

Zhang Yufei roared into the 100m butterfly final on Wednesday morning with the year's third-fastest time -- she also owns the fastest -- bolstering her case as hot favorite in Paris.

The 25-year-old, who has already claimed the 200m fly title in Hangzhou to go with her Olympic gold, surged to the wall in a Games-record 56.20sec.

A 100m butterfly silver medallist at the Tokyo Olympics two years ago, behind Maggie Mac Neil, Zhang turned the tables at the world championships in July by edging the Canadian to win gold.

In other sports, Chinese table tennis legend Ma Long, 34, said he had almost certainly made his last Asian Games appearance after helping the hosts to men's team gold.

Asked about the prospect of defending his Olympic title next year, Ma said: "Paris is still too early to say for me."