Kenya, Ethiopia, Japan and Team USA Highlight Deep Fields
BOULDER, Colo. – BOLDERBoulder announced the rosters for the International Pro Team Challenge. Athletes from the United States and five other countries will toe the line on Memorial Day, Monday, May 25, competing for more than $100,000 in prize money and available bonuses. The individual men’s and women’s champions will each earn a minimum of $10,000.
BOLDERBoulder, named “America’s All-Time Best 10K” by Runner’s World, created the International Pro Team Challenge in 1998 and annually hosts some of the world’s fastest professional distance runners representing their countries in a team-scored competition. Since 1986, 112 Olympians have competed at the BOLDERBoulder with more than $4.4 million in prize money awarded.
We are incredibly excited about the depth and international quality of this year’s professional fields. From Olympians and national record holders to rising young stars, this year’s International Pro Team Challenge truly reflects the global stature of the BOLDERBoulder. The matchups on both the men’s and women’s sides should create some incredibly competitive racing for our fans in Boulder and viewers watching around the world. – Cliff Bosley, BOLDERBoulder race director
Men’s International Team Challenge – Team Rosters & Athlete bios
The men’s race will showcase one of the strongest fields in event history. While three-time defending champion Conner Mantz will not compete this year due to injury, fans will once again see Daniel Simiu Ebenyo on the starting line after his dramatic runner-up finish in 2025. Ebenyo led much of last year’s race and appeared headed for victory before Mantz surged past him over the final 50 meters in one of the most iconic finishes in BOLDERBoulder history. Joining Ebenyo on Team Kenya will be Athanas Kioko, who finished seventh at last year’s race, and Patrick Kiprop, the 2025 Peachtree Road Race champion who resides in Boulder and trains with the On Athletics Club.
The United States will field three men’s squads led by Team USA Red, featuring Clayton Young, Jared Ward, and Casey Clinger. Training teammates based in Provo, all three are graduates of Brigham Young University and have emerged as some of the top American distance runners in the country. Young recently placed 11th at the 2026 Boston Marathon in 2:05:41, while Ward finished ninth at the USATF 10 Mile Championships. Clinger, the American record holder in the 25 km, recently placed third at the USATF 25 km Championships.
Team USA White brings another formidable trio with Ryan Ford, Graydon Morris, and Aiden Reed. Ford, a recent transplant to Boulder, finished 12th at this year’s Boston Marathon in 2:05:47, while Morris won the USATF 10 Mile Championships. Reed, a Boulder resident, finished third at the USATF 10 Mile Championships and fifth at last year’s BOLDERBoulder International Team Challenge one year after winning the BOLDERBoulder citizens race.
Representing the Boulder running community and an all-University of Colorado Boulder alumni team will be Team USA Blue featuring Andy Wacker (CU ’12), Conner Winter (CU ’16), and Stephen Jones (CU ’22). Wacker finished sixth at the recent USATF 25 km Championships, while Winter placed seventh at the USATF 10 Mile Championships in April.
Japan returns to the with its first men’s team since 2019, led by Japanese record holder Suguru Osako, alongside Kengo Suzuki and Kiyoto Hirabayashi. Osako owns the Japanese marathon record at 2:04:55, while Suzuki ranks second all-time in Japanese history at 2:04:56. Hirabayashi enters the race with a marathon personal best of 2:06:14 after placing fifth at the Osaka Marathon in February.
Additional international teams include Eritrea’s Amanuel Mesel and Tesfu Tewelde, Mexico’s Hesiquio Flores, Julio Alberto Ortiz Ponce, and Luis Vázquez, and Morocco’s Abdelkarim Ben Zahra, Rahal Bouchfar, and Mohammed El Youssfi. El Youssfi recently captured victories at the Cherry Blossom 10 Mile in Washington and the Gate River Run in Jacksonville and is expected to contend for the win in Boulder.
Women’s International Team Challenge – Team Rosters & Athlete bios
A new women’s champion will also be crowned as two-time defending champion Grace Nawowuna will not return due to injury, opening the door for one of the deepest international women’s fields in recent event history.
Kenya enters the race as one of the favorites led by Jesca Chelangat, who recently placed second at the Prague Half Marathon in 1:06:45. She will be joined by Evaline Chirchir, sixth at the Houston Half Marathon in 1:07:26, and Rebecca Mwangi, who represented Kenya at the World Cross Country Championships earlier this year.
Ethiopia also brings a formidable lineup capable of challenging for both the individual and team titles. The squad is led by Buze Diriba, who finished third at the Houston Half Marathon earlier this year in 1:05:57 after winning the 2025 Frankfurt Marathon in 2:19:34, alongside Axumawit
Embaye, who recently finished fifth at the Lille 10K in a blistering 30:22 – the fastest 10K personal best in this year’s field – and rising 21-year-old Lemlem Nibret, who recently competed at the World Cross Country Championships.
Team USA Red is expected to contend for the team title behind a trio of emerging American stars in Bailey Hertenstein, Kassie Parker, and Rachael Rudel. Hertenstein, a 2024 graduate of University of Colorado Boulder, recently placed eighth at the USATF 5 km Championships in 15:24. Parker enters the race in outstanding form after winning the Bloomsday Lilac Run and placing second at the USATF 25 km Championships earlier this spring. Rudel, a 2017 graduate of Colorado State University who resides in Fort Collins, finished second at Bloomsday.
Team USA White features an all-Colorado resident lineup led by Biruktayit Degefa, Sara Vaughn, and Molly Grabill. Degefa recently placed third at both the Houston Marathon and the USATF 25 km Championships, while Vaughn continues to be one of the most accomplished masters athletes competing at the elite level in the United States. Grabill holds the BOLDERBoulder citizens race record after running 33:39 two years ago.
Brazil returns with a veteran trio featuring Tatiane Raquel da Silva, Simone Ferraz, and Jenifer Silva.
Mexico’s team includes Anahi Alvarez, Adela Honorato, and Natalí Naomi Mendoza, while Morocco will be represented by Hafssa Boutrich, Meryeme Mai, and Oumaima Saoud, who recently placed second at the 2026 Marrakesh Marathon.
The women’s professional race is scheduled to begin at 11:15 a.m., followed by the men’s race at 11:26 a.m. The races can be viewed locally on Denver7 and streamed worldwide on the BOLDERBoulder YouTube channel.