Last year, when the race was held under the pall of Sept. 11, Jifar won the men's marathon in 2 hours, 7 minutes, 43 seconds, setting a course record. Okayo also produced a course record when she claimed the women's race in 2:24:21.
Jifar, who was making his New York marathon debut, bested the 2:08:01 run of 1989 winner Juma Ikangaa of Tanzania. Okayo beat the mark of Australian Lisa Ondieki, who completed the 1992 race in 2:24:40.
Skipping the event are world record-holders Khalid Khannouchi of the United States and Paula Radcliffe of Britain. Khannouchi ran in Chicago three weeks ago, as did Radcliffe, who broke the world's best by more than a minute, winning in 2:17:18.
The 26.2-mile course through New York's five boroughs is considered too difficult to elicit world marks. More than 24,000 runners traverse five bridges in front of 2.5 million spectators, usually under seasonably chilly conditions.
Blinded in his right eye at age 12 by a bull's horn, Jifar will be trying to become the race's seventh repeat winner, but has not had the best preparation. He has not raced at any distance in six months after overtraining for the London marathon.
The 26-year-old was fourth in a half-marathon at Lisbon, Portugal in March, ninth at London in April and fifth at the World Half-Marathon Championships in May.
Jifar will be challenged by Rogers Rop of Kenya, who won the Boston marathon in April, and Stefano Baldini, the Italian who has the field's fastest time of 2:07:29.
Meb Keflezighi perhaps represents the United States' best hope. Keflezighi, the American record-holder at 10,000 meters, will be making his marathon debut.
An American man has not triumphed in New York since Alberto Salazar claimed the last of three straight titles in 1982.
Okayo, 26, has been one of the most consistent marathoners over the last few years. Her victory over Catherine Ndereba of Kenya in the Boston marathon in 2:20:43 smashed the course mark and ranks as the sixth-fastest marathon ever.
Okayo has won her last three races. A third-place finisher here two years ago and runner-up in Chicago in 1999, she won Italy's Giro Di Pettinengo 4km on Oct. 13 and Lisbon's Oni Meia-Maratona half-marathon.
Making her New York debut, Kiplagat has recorded the second and third fastest 10km of the year. She also set a 10-mile world best in Zaandam, the Netherlands in late September. The Kenyan began her season with a victory at the Osaka marathon in 2:23:55 in January.
The female with possibly the strongest major race credentials is Joyce Chepchumba, who won the London marathon in 1997 and 1999, the 1998 Chicago and 2000 Tokyo titles. She also claimed the Olympic bronze medal in Sydney and came in sixth at London this year.
Other threats include Olympic 5,000 silver medalist Sonia O'Sullivan of Ireland, defending runner-up Susan Chepkemei of Kenya and 2000 champion Ludmila Petrova of Russia.
Marla Runyan, a legally blind Olympian and two-time U.S. 5,000 champion, will make her marathon debut.
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