Kenyan marathon runner Eliud Kipchoge is chasing the final piece of his Olympic medal collection at the Rio 2016 Olympic Games but has made a big leap in distance to try to achieve it.

Kipchoge has a 5000m silver medal from Beijing 2008 and a bronze in the same event at Athens 2004. He missed selection for London 2012 and then made the switch to marathon. He has been the outstanding road runner since then.

Both the men's and women's marathon at Rio 2016 will start and finish at the Sambodromo - the purpose built parade facility for carnival in Rio.

 Kipchoge won silver at the Delhi 2010 Commonwealth Games behind Moses Ndelema Kipsiro of Uganda (Getty Images/ Michael Steele)

The race immediately heads towards Centro, the financial heart of the city, before running past the airport and along the shoreline to Botafogo Beach. A few laps follow, before the runners head back to Centro and home to the finish line at the Sambodromo.

Those seeking to deny Kipchoge a celebratory samba on the home straight include countryman Stanley Biwott, Eritrean Ghirmay Ghebrealassie and London 2012 Olympic champion Stephen Kiprotich of Uganda.

For the women, the name Dibaba should feature in the distance running medals again, but this time it is no relation to the other great Ethiopian Tirunesh Dibaba, the three-time Olympic champion in 5,000 and 10,000 in the last two Games.

Rather it is Mare Dibaba, who won the marathon at the world championships in Beijing last year, albeit in a sprint finish against Kenyan Helah Kiprop, with only one second separating them. The Kenyan will be in Rio to seek her revenge.