Michael Phelps's coach says swimming's biggest star should not compete again until the sport's governing body bans the use of controversial new suits.
Phelps lost his first major race since 2005 to Paul Biedermann, who wore a suit Fina will make illegal in 2010.
So far 11 world records have fallen at the World Championships to swimmers in contentious 100% polyurethane outfits.
Bob Bowman said he would tell eight-time Olympic champion Phelps "not to swim until the rules are implemented".
Phelps, whose dominance in the pool at the Beijing Oympics sparked an upsurge of interest in the sport, still wears a Speedo LZR suit, which is 50% polyurethane and has been superseded by a new generation of hi-tech bodysuits.
The 24-year-old American was beaten in the 200m freestyle final in the World Championships in Rome on Tuesday by Germany's Biedermann, who was wearing an all-polyurethane suit and took Phelps's world record in the process.
Fina have agreed to ban the performance-enhancing suits next year but this ruling may not come into effect until April or May and Bowman feels this is not soon enough.
"I'm done with this. It has to be implemented immediately. The sport is in shambles right now and they better do something or they're going to lose their guy who fills these seats," he said.
RECORDS IN ROME
Day One (six records): M 400m free Paul Biedermann (Arena X-Glide) W 200m IM Ariana Kukors (Jaked 01) W 4x100m free (2) Netherlands AND Britta Steffen broke 100m free on her leg (Adidas Hydrofoil) W 100m butterfly Sarah Sjostrom (Arena X-Glide) W 400m free Federica Pellegrini (Jaked 01)
Day Two (five records): W 100m butterfly Sarah Sjostrom (Arena X-Glide) W 200m IM Ariana Kukors (Jaked 01) W 100m breaststroke Rebecca Soni (Arena X-Glide) W 100m backstroke Anastasia Zueva (Arena X-Glide) M 100m breaststroke Brenton Rickard (Jaked 01)
Day Three (four records): W 100m backstroke Gemma Spofforth (Speedo LZR) W 200m Freestyle Federica Pellegrini (Jaked 01) M 50m breaststroke Cameron Van Der Burgh (Arena X-Glide) M 200m freestyle Paul Biedermann (Arena X-Glide)
Day Four (seven records): W 200m butterfly Mary Descenza (Jaked) M 50m breaststroke Cameron Van Der Burgh (Arena X-Glide) M 200m butterfly Michael Phelps (Speedo LZR) W 200m freestyle Federica Pellegrini (Jaked 01) W 50m backstroke Daniela Samulski (Speedo LZR) W 50m backstroke Anastasia Zueva (Arena X-Glide) M 800m freestyle Zhang Lin (Speedo LZR)
"We've lost all the history of the sport. Does a 10-year-old boy in Baltimore want to break Paul Biedermann's record? Is that going to make him join swimming?
"It took Michael from 2003 to 2008 to go from 1:46 to 1:42.9 and this guy's done it in 11 months. That's an amazing training program. I would love to know how that works."
Biedermann clocked one minute 42.00 seconds, which beat Phelps' world mark of 1:42.96 from the Beijing Olympics.
On Monday, Biedermann also broke the men's 400m freestyle record, which was held for seven years by Australian Ian Thorpe.
The German has improved on his personal best by almost seven-and-a-half seconds since he started using the suit.
Phelps praised Biedermann's achievement, but looked forward to a time when the banning of 100% polyurethane suits returns swimming to an even contest.
"Paul is a very strong swimmer and has had an excellent year," said Phelps. "I have not been beaten by the swimsuit but by a great athlete.
"However, a solution needs to be found to the issue of swimsuits as this is not swimming any more.
"Technology has to go forward but I am looking forward to the time when we can go back to pure swimming.
"I will start working as soon as I can and I am confident that I will be in my best shape for the next major competitions, particularly for London [2012 Olympics]."
On Tuesday, a Fina committee upheld last week's decision by the wider organisation to restrict males to suits that go from the waist to the top of the knees, while female suits cannot go past the shoulders or beyond the knees, from next year.
What Fina's top officials have done to the sport, what they have allowed to happen, is an absolute disgrace
In addition, Fina also announced that suit materials will be restricted to "textiles", a definition which will be determined by a scientific committee, and that there will be specific standards for buoyancy, thickness and permeability.
The complete rules will be given to swimsuit companies by 30 September.
"The rules will be applied in 2010. That can be April or May. It depends on the time manufacturers need to pass from polyurethane to textiles," said Fina executive director Cornel Marculescu.
The controversy began at the start of 2008 when swimmers began to wear the part-polyurethane Speedo LZR suits.
At the Beijing Olympics 23 of the 25 world records set were by swimmers wearing the new attire and by the end of the year 108 new world marks had been set by those wearing the suit.
Since swimmers began to wear the 100% polyurethane suits - the Jaked 01, Arena X-Glide and Adidas Hydrofoil to name but a few - 49 world records have fallen up to and including the third day of the World Championships.
"I would be perfectly happy if we adjust all the records starting with the LZR. If we took them all out and went back to 2007," said Bowman.
"Even those in Beijing. We can have them in a separate list. These were done in polyurethane suits and then these are done in textile suits. Then we can start over in January and make the sport about swimming."
Three-time Olympic champion Grant Hackett has branded Fina an "absolute disgrace" for allowing the polyurethane suits at the World Championships.
The Australian's 1500m freestyle marks is the only pre-bodysuit record still standing.
"New leadership is needed to look after the sport. I'm furious at Fina," said the Australian, who retired in 2008.
Speaking about Biedermann's new mark in the 400m freestyle, Hackett told The Australian Newspaper: "I hate saying this because I sound like a bad sport, but that world record would not have gone without that suit.
"What Fina's top officials have done to the sport, what they have allowed to happen, is an absolute disgrace."
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