Paula Radcliffe's comeback delayed

MANCHESTER, England -- Marathon world record-holder Paula Radcliffe's comeback has been delayed after she was forced to withdraw from a race this month because of bronchitis.

The 37-year-old Radcliffe had been set to run May 15 in the 10-kilometer Great Manchester Run, but says she is not ready to compete.

Radcliffe's last race was the 2009 New York Marathon. She then took time off to prepare for the birth of her second child, Raphael.

Radcliffe says "frustrated as I am, I know that the main focus for me is next year's Olympic marathon and achieving a qualifying standard later this year."

Radcliffe also says she is being particularly careful in her recovery because of possible complications with her asthma.