-- LONDON -- The World Marathon Majors series says it has postponed Sunday's awards ceremony because Kenyan runner Rita Jeptoo has tested positive for doping.
Jeptoo's agent confirmed the failed doping test Friday afternoon.
The series says "no athlete can win the World Marathon Majors Series title who has been in breach of IAAF anti-doping rules."
The website RunBlogRun had posted earlier Friday about the 33-year-old Jeptoo testing positive in an out-of-competition test in September, a few weeks before winning her second straight Chicago Marathon title. Jeptoo has also won the past two Boston Marathons. She was scheduled to receive her $500,000 prize for winning the World Marathon Majors this weekend in New York.
Jeptoo's coach Claudio Berardelli met with reporters at the New York City Marathon expo and said he knows that 99 percent of his athletes are clean.
"I'm still a little bit shocked about Rita," Berardelli said.
The IAAF has not yet made an announcement on the case.
Jeptoo tested positive for EPO, according to an Athletics Kenya official. Jeptoo has denied ever taking a banned substance.
ESPN.com contributor Christopher Chavez and The Associated Press contributed to this report.