Magnussen, who won the 100 meters freestyle at the 2011 and
2013 world championships but suffered an agonizingly close
defeat to Adrian in the 2012 Olympic final, has been troubled by
back pain for the past few weeks.
He finished third in the 100m at last month's Pan Pacific
championships in his homeland then withdrew from the 50m sprint
and was told by doctors to rest his back and avoid flying until
it was healed.
"I am very disappointed to not be able to compete," Magnussen
said in a statement.
The inaugural Singapore Swim Stars features some of the sport's
most accomplished stars, who will be racing for cash prizes
rather than medals.
(Reporting by Julian Linden; editing by Amlan Chakraborty)
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