Sprint showdowns scuttled at Prefontaine meet

Christian Coleman will not have a 100m world championship rematch with Justin Gatlin at Saturday's 44th Prefontaine Classic nor will he face Noah Lyles in a 200m showdown at his Diamond League debut.

The 22-year-old American star was to have faced both star rivals at the Eugene, Oregon, meet in his season opener after winning this year's world 60m indoor crown at Birmingham and finishing second to Gatlin in last year's world outdoors 100m final at London.

But 2004 Olympic and 2005 world champion Gatlin, 36, withdrew from the 100 to foil what would have been his first meeting with Coleman since they both outraced third-place Usain Bolt in the Jamaican star's last individual race.

That prompted Coleman to pull out of a 200m matchup against Lyles, the Diamond League leader after winning at Doha earlier this month in a personal best of 19.83 seconds, and run only the Pre 100m, according to a Twitter posting from manager Emanuel Hudson.

"Coleman set to run the 100m @nikepreclassic, earlier mgmt considered a 100/200m double," the HSI Sports Agency tweet said. "being his first race of the season, it is more prudent to only contest the 100m. His opening 200m will occur in @BislettGames."

Coleman's 100m rivals are set to include two-time African champion Ben Youssef Meite of Ivory Coast, US 60m indoor champion Ronnie Baker, Britain's reigning Diamond League champion Chijindu Ujah and China's Su Bingtian, who ran a wind-aided 9.92 at last year's Pre after becoming the first Asian-born runner to break 10 seconds with a 9.99 on the same track in 2015.

Baker owns the fastest time in the world this year with a 9.97 last month.

Facing 20-year-old former world junior champion Lyles in the 200 will be reigning world champion Ramil Guliyev of Turkey, reigning US champion Ameer Webb, last month's Commonwealth Games winner Isaac Makwala of Botswana and 2017 world third-place finisher Jereem Richards of Trinidad and Tobago.

Reigning world and Olympic women's pole vault champion Katerina Stefanidi of Greece, seeking her third consecutive Diamond League crown, will be tested by American Sandi Morris, the world and Olympic runner-up who leads this season's Diamond race after winning at Doha.

Reigning men's shot put world champion Tomas Walsh of New Zealand, coming off Commonwealth Games and world indoor titles earlier this year, will face reigning Olympic champion Ryan Crouser of the United States.

Rio Olympic 100m women's champion Elaine Thompson of Jamaica, chasing her third Diamond League crown, faces reigning world champion Tori Bowie of the United States in the women's sprint classic.

Reigning women's 400 world champion Phyllis Francis of the United States will face reigning Olympic champion Shaunae-Miller Uibo of the Bahamas with Rio Olympic runner-up and former world champion Allyson Felix and fellow American Courtney Okolo, this year's world indoor winner contenders in a stellar field.

Olympic and world champion Caster Semenya opens pursuit of a third consecutive Diamond league crown in the women's 800m.