Mo Farah returns to the Prefontaine Classic 10,000m and the Olympic gold medallist will be joined by another incredibly deep field at the IAAF Diamond League meeting on 29-30 May.Held on the eve of the main competition in Eugene, the men&rsquo;s 10,000m is once again a cornerstone of &lsquo;Distance Night&rsquo;.Farah has been the world&rsquo;s most dominant long-distance track runner since he won the 5000m gold and 10,000m silver at the 2011 IAAF World Championships; his last loss at the longest distance on the track. He followed that up by taking the 5000m and 10,000m titles at both the 2012 Olympics and 2013 World Championships.At the 2011 edition of the Pre Classic, Farah set a European record of 26:46.57 to win the highest quality 10,000m race in history. He was one of a record nine runners in that race to run faster than 27 minutes.A record seven runners enter this year&rsquo;s Pre Classic with PBs faster than 27 minutes &ndash; and that does not include the reigning world cross-country champion.World bronze medallist Paul Tanui has twice set a PB in Eugene, with last year&rsquo;s 26:49.41 clocking making him the fastest Kenyan in three years.Josphat Bett won the Kenyan 10,000m title last year, then went on to take silver at the Commonwealth Games and bronze at the African Championships. The 2008 world junior champion set his PB of 26:48.99 when finishing third in Eugene in 2011.Emmanuel Bett, no relation to Josphat, finished fourth in Eugene in 2012 in a race which doubled as the Kenyan Trials. He missed making the Olympic team by two seconds, but won in Brussels later that year with a world-leading 26:51.16, a time which remains his PB.Geoffrey Kamworor of Kenya is not only the reigning world cross-country champion, but also the world half-marathon champion. Kamworor was only 18 when he ran his first 10,000m, a still-standing PB of 27:06.35 from the 2011 edition of the Prefontaine Classic.Kenneth Kipkemoi won the African 10,000m title in 2012. Like Emmanuel Bett, he missed out on making the Kenyan Olympic team in 2012, but finished the year with a PB in Brussels, clocking 26:52.65. He then finished seventh at the 2013 World Championships.Geoffrey Kirui was just 18 years old when he clocked his 10,000m PB of 26:55.73 in 2011, making him the second-fastest junior in history. The Kenyan won the African junior title earlier that year, and then went on to take bronze at the 2012 World Junior Championships.Titus Mbishei earned silver medals in the 10,000m at the 2008 World Junior Championships and in the junior race at the 2009 World Cross Country Championships. His PB of 26:59.81 was set in 2011 when he was just 20 years old.One year after taking junior silver at the 2013 World Cross Country Championships, Leonard Barsoton won the senior African cross-country title at the age of 19. Later that year he set a 10,000m PB of 27:20.74 and then finished fifth in the senior race at this year&rsquo;s World Cross Country Championships.Teklemariam Medhin has earned two individual medals at the IAAF World Cross Country Championships. The two-time Olympic finalist has a 10,000m PB of 27:16.69.Uganda&rsquo;s Joshua Cheptegei will return to Hayward Field after winning the world junior 10,000m title in the same stadium last year. Still just 18 years old, he has already won the African junior title this year.The top North American in the field is Cam Levins. A training partner of Farah, the Canadian took bronze at the Commonwealth Games last year. His 10,000m PB of 27:27.96 was set on his debut at the distance in 2012.His PB of 27:28.10 might not be the fastest in the field, but Eritrea&rsquo;s world and Olympic finalist Nguse Amlosom won the hotly contested African title over 10,000m last year.William Sitonik, the 2011 world youth 3000m champion, has already won two 10,000m races this year, both in Japan. This will be his first race on US soil.World University Games champion Stephen Mokoka won both the 10,000m and 5000m at this year&rsquo;s South African Championships, setting a national record of 13:11.44 in the latter. Like Sitonik, the 30-year-old will be making his US racing debut.Since setting a PB of 27:32.96 in Eugene last year, 35-year-old El Hassan El Abbassi of Bahrain has won the 2014 Asian Games and 2015 Arab Championships at the distance.Suguru Osako took the silver medal behind Al Abbassi at the 2014 Asian Games. Earlier this year he set Japanese indoor records at 3000m, two miles and 5000m.Others in the field include Uganda&rsquo;s Timothy Toroitich, 2009 world youth 3000m bronze medallist Goitom Kifle of Eritrea, 2010 Kenyan 5000m champion Vincent Yator, Commonwealth 5000m bronze medallist Zane Robertson of New Zealand, 2012 European 5000m silver medallist Arne Gabius, and Moroccan 10,000m debutant Othmane El Goumri.National half-marathon champion Diego Estrada and 13:02.80 5000m runner Hassan Mead are the two US entrants in the field.Organisers for the IAAF2015 IAAF Diamond League calendar Doha, QAT &ndash; 15 May Shanghai, CHN &ndash; 17 May Eugene, USA &ndash; 30 May Rome, ITA &ndash; 4 June Birmingham, GBR &ndash; 7 June Oslo, NOR &ndash; 11 June New York, USA &ndash; 13 June Paris, FRA &ndash; 4 July Lausanne, SUI &ndash; 9 July Monaco, MON &ndash; 17 July London, GBR &ndash; 24-25 July Stockholm, SWE &ndash; 30 July Zurich, SUI &ndash; 3 September Brussels, BEL &ndash; 11 September

Mo Farah returns to the Prefontaine Classic 10,000m and the Olympic gold medallist will be joined by another incredibly deep field at the IAAF Diamond League meeting on 29-30 May.

Farah to face Kamworor in loaded Eugene 10,000m – IAAF Diamond League

After a stellar track career and success over 10km on the roads, Kenya’s 2009 world 10,000m champion Linet Masai will make her half marathon debut at Sunday’s Great Birmingham Run, an IAAF Silver Label Road Race, where she faces France’s European marathon champion Christelle Daunay.Masai, the four-time world cross-country medallist, heads to the English West Midlands following a relatively quiet year, during which she has focused exclusively on road racing. The 24-year-old will be encouraged, however, by a first victory in 2014 in Amsterdam last month, where she prevailed over 10 miles in 53:09.Daunay, on the other hand, has enjoyed the best season of her long career. The 39-year-old French national record-holder for both the half and full marathon drops down in distance from the event at which she took a fine gold medal in Zurich this summer and returns to racing over 13.1 miles for the first time since she won in 1:09:17 in the Czech Republic in May.The 2009 New York Marathon third-place finisher finished second to Italy’s Valeria Straneo in Paris over 10km earlier this month and will be tough to beat on a hilly course that in many ways mirrors the one on which she triumphed back in August.Daunay’s predecessor as European marathon champion, Italy’s Anna Incerti, is also in the race, as are Portugal’s Ana Dulce Felix and Kenya’s Doris Changeywo. The latter was a silver medallist at the 2010 Commonwealth Games but hasn’t competed internationally since 2012, while Dulce Felix, the 2012 European 10,000m champion and a regular on the British roads, is using the event to prepare for next month’s New York Marathon.Incerti, who was sixth behind Daunay in Zurich, won comfortably over 10km in Milan two weeks ago and, with a personal best of 1:08:08 from 2012, could challenge.Uganda’s Thomas Ayeko returns to defend his title in the men’s race, but faces tough opposition in the form of Kenyan 10,000m champion Josphat Bett.Ayeko appeared to be on the verge of a big breakthrough when he surged clear in the latter stages of last year’s race on his half marathon debut, but he has raced sparingly in 2014 and failed to make an impression over 5000m and 10,000m at the African Championships in August.A fifth-place finish in 1:02:13 on his return to the roads at the Great North Run in September hints at a return to form for the 22-year-old, who will need to be at his best to see off the challenge of Bett, who himself will be hoping to improve on a fourth-place finish over 10 miles in Amsterdam four weeks ago.Bett, the 2008 world junior 10,000m champion, took medals at both the Commonwealth Games and the African Championships over 10,000m this summer and has a half marathon best of 1:01:01, which is more than a minute quicker than his Ugandan rival’s strongest performance.Both will have to be wary of the threat posed by Bett’s 31-year-old namesake, Emmanuel, who won the 2013 Great South Run in challenging conditions and has a personal best of 1:00:56 set two years ago.Indeed, the veteran Kenyan boasts an impressive list of best performances ranging from two miles upwards and ran 13:14.91 for 5000m as recently as July.Home support will be focused on Steve Way, the 40-year-old ultra-distance runner who finished 10th in the marathon at this year’s Commonwealth Games, while Kenya’s Kevin Kochei and Joel Kimutai have both competed well over 13.1 miles this year. The former in particular has raced prolifically and finished seventh at the recent Great Scottish Run.Dean Hardman for the IAAF

After a stellar track career and success over 10km on the roads, Kenya’s 2009 world 10,000m champion Linet Masai will make her half marathon debut at Sunday’s Great Birmingham Run, an IAAF Silver Label Road Race, where she faces France’s European marathon champion Christelle Daunay.

Farah to face Kamworor in loaded Eugene 10,000m – IAAF Diamond League

Masai hopes for debut to remember in Birmingham