Can Mo Farahcomplete his third consecutive global 5000m/10,000mdouble? Can Eunice Sum help to keep Kenya at the top of the medals table by retaining her 800m title? And will the final meeting here between Usain Bolt and Justin Gatlin, in the men’s 4x100m relay, see US pride partly restored after the Jamaican’s individual 100 and 200m victories.

These questions, and many more, will be answered in the course of a program which involves eight medal events – as well as those above, golds will be given for the men’s50km race walk, the women’s high jump, the men’s discus, the decathlon and the women’s 4x100m relay. Don’t blink or you’ll miss something.

Farah, who has already retained his 10,000m title, will have the rising talent of Ethiopia’s18-year-old world junior champion, YomifKejelcha, to deal with if he is to win the 5000m again. Other threats include training partner Galen Rupp of the theUnited States and Kenya’s Caleb Ndiku.

The sum has a battle on her hands, given the form shown in the semi-finals by Canada’s top qualifierMelissa Bishop, who ran a national record of 1:57.52, and Marina Arzamasova of Belarus, who set a personal best of 1:57.54, plus the lurking threat of SifanHassan of the Netherlands, the 15oom bronze medallist here.

As for the men sprint relay – the US earned the bragging rights as they beat a Jamaicanquartet including Usain Bolt at the IAAF World Relays in the Bahamas.  The difference here could be that Bolt is coming off two demoralizing victories, and the 33-year-old Gatlin has already been talking about the fatigue in his legs…

Jamaica’s women maintained their dominance over the United States in the Bahamas but will be hard-pressed to defend their title. Good news though is that 100m championShelly-Ann Fraser-Pryce will have fresh legs having foregone to defend her 200mtitle here.

After two Olympic silvers and two world bronzes, could this be the opportunity for Australia’s 30-year-old 50km racewalker Jared Tallent to earn a first global gold? China’s trio of Qianlong Wu, Wei Yu, and Lin Zhang will want to add to the walking medals already won by their nation.

Russia’s Olympic high jump champion Anna Chicherova, who leads this year’s world lists with2.03m,  looks in the right form to claim another global title, with fellow Russian MariyaKuchina, the joint world indoor champion, Ruth Beitia of Spain and former world champion Blanka Vlasic her main challengers.

In the meniscus, Poland’s Piotr Malachowski is poised to take advantage of the absence of Germany’s three-times champion Robert Harting through injury. But top qualifier Fedrick Daces will prove challenging – as will Harting’s younger, but bigger brother, Christoph, hoping to keep the title in the family.

A stunning45.00sec 400m run – taking more than half a second off his best – left AshtonEaton in the ideal position to defend his decathlon title. In his first decathlon since Moscow 2013, the American leads by more than 300 points with an overnight total of 4703.