Australian sprinter Michael Klim felt like celebrating before hitting the wall after burning off his rivals to win the men's 200 metres freestyle gold medal at the World Swimming Championship in Perth yesterday.

The shaven-headed 20-year-old destroyed the world's best to win Australia's first-ever medal in the event, less than a second outside the world record.

Klim, who went into the race the top-ranked swimmer, was under world record pace for the first three turns before finishing in one minute 47.41 seconds - 72 hundredths of a second outside the eight-year world record held by Italian Giorgio Lamberti, the longest-lasting record in men's swimming.

Australia was one of four nations to win gold medals on the opening night of the swimming competition.

The brilliant Yan Chen threatened to shatter her world record at one stage on the way to claiming China's first gold medal of the meet in the women's 400 metres individual medley.

Yan Chen clocked 4:36.66 to beat Ukranian 15-year-old Yana Klochkova (4:38.60) and Japanese 16-year-old Yasuko Tajima (4:39.45).

Her victory was politely observed by the crowd, dispelling immediate fears that the Chinese would be booed and jeered during the medal ceremonies after her teammate Yuan Yuan was arrested for carrying a banned human growth hormone into the country last week.

Yan Chen, who smashed East German Petra Schneider's drug-tainted 15-year world record during the Chinese national championships in Shanghai last October, surged home over the last three laps to take gold.

America's five-time Olympic relay gold medallist Jenny Thompson won her first individual gold medal at a major meet with success in the women's 100 metres freestyle.

Thompson came from third at the turn to take the gold medal in 54.95 seconds from Slovakia's multi 1997 World Student Games gold medallist Martina Moravcova (55.09 seconds) and China's Ying Shan (55.10).

Belgian Fred Deburghgraeve added a world 100 metres breaststroke crown to the Olympic title he won at Atlanta in 1996 with an all-the-way victory in 1:01.34 from China's Quiliang Zeng (1:01.76) and American Kurt Grote (1:01.93).

But it was the last event of the opening night which almost offered a world record as Klim churned away to burn off the field with a sensational set of sectional times.

Klim's sectional times were 24.97 seconds for the first 50 metres, 52.07 for the 100 metres and 1:19.49 at the 150-metre mark.

It was only in the last 20 metres that the Polish-born Klim began to fade, but, as he said at his press conference, he still has to reserve his energies for his remaining six swims at the championship.

"I'm really enjoying the moment and it's right up there with my butterfly world record," said Klim. "I can't do everything at once and I've got to leave something in reserve for my remaining swims, the 200 metres relay tomorrow night is very important for Australia."

Klim said he "unfortunately started to celebrate before touching the wall," and that when he was a half-body length ahead at the last turn, he knew the race was his.

A special moment for Klim was meeting nine-time Olympic champion Mark Spitz just before he entered his post-swim press conference.

After five Olympic relay gold medals, 24-year-old Thompson finally did it on her own in the 100 metres freestyle, coming from behind German Sandra Voelker and teammate Amy Van Dyken after the first lap to win the opening event.

"I've never won an individual gold medal at the world's or the Olympics, so I'm ecstatic," she said. "At first, I didn't think I'd won because I heard Martina (Moravcova) scream for joy."

Deburghgraeve is looking forward to the Sydney Olympics in 2000 after his breaststroke win. The Belgian, who plummeted in the rankings last year to 62nd in the world, surged back into contention yesterday, streaking home in the final and beating off world number three Zeng.

Meanwhile, because of delays, FINA, swimming's world governing body, have been unable to announce what ban Chinese breaststroker Yuan Yuan and her coach Zhou Zhewen will serve for their parts in bringing a banned substance into the country last week.

The doping panel verdict is expected today, with Australian officials hitting back at claims yesterday that the delay was caused because customs officers, who uncovered the haul, had taken the weekend off.