A glum Michael Phelps pulled out of the world short course championships with a back injury on Friday, casting concern on his swimming future.
Phelps arrived here on Wednesday looking for a repeat of his six gold medals at the recent Athens Olympics but left two days later not knowing when he would compete again.
The 19-year-old American will return home to Baltimore for further evaluation and treatment. The injury flared up on Thursday after Phelps won the 200 metres freestyle and then worsened overnight.
The U.S. team issued a statement early on Friday saying he had withdrawn from the 400m individual medley heats but would receive treatment during the day and hoped to swim the relay later in the evening.
When his back did not respond to treatment, team doctor Jim Johnson consulted with experts and made the decision to pull Phelps out of the entire meeting.
"As the medical director for USA Swimming, I have elected to withdraw Michael from the remainder of this competition," Johnson told reporters. "He has a slight back injury...and we don't want to take the risk of it worsening over the next three days.
"He's 19, he's got a long career ahead of him and we don't want to take any undue risk to his health."
A concerned Phelps said he accepted the decision of the doctors and wanted to take every precaution having seen first hand how a back injury can end a career.
PREMATURE RETIREMENT
Phelps's older sister Whitney was also a top swimmer until back problems forced her into premature retirement.
"My sister was a world class swimmer and had back injuries and it put her out of swimming," said Phelps. "These guys (doctors) know what they're talking about.
"I agree with them 100 percent. If this is something that could hurt my future in the sport, then this is the best decision.
"Hopefully I have a long career ahead of me and we can get this thing worked out.
"It is something you have to be really cautious with...your back especially."
Phelps said his back had been bothering him for about 10 days but along with Johnson was evasive when asked for specifics about the injury, refusing to give details.
"I would rather not discuss it but it is my back," said Phelps. "I just don't want to go into too many details, we're not really sure what it is.
Earlier Report
Phelps makes a winning return
"It felt decent coming into the meet but it started tightening up right after we got off the plane.
"I wanted to play it by ear and get in the water and swim and see what would happen."
The charismatic teenager was the main attraction of the meet and was scheduled to swim in all 10 sessions in the temporary pool constructed on the floor of the cavernous Conseco Field House, home of the NBA's Indiana Pacers.
