Britons Scott Overall and Freya Ross among those in action at the Bank of America Chicago Marathon

Dickson Chumba and Florence Kiplagat return to the Bank of America Chicago Marathon on Sunday (October 9) looking to retain their titles.

Chumba won the men's race in 2:09:25 one year ago, while Kiplagat took the women's title in 2:23:33.

Chumba is the quickest in the field with his PB of 2:04:32 and he will face a line-up including fellow Kenyan and two-time world champion Abel Kirui and their countryman Micah Kogo, plus Ethiopia's Abayneh Ayele, who placed fourth at the IAAF World Half Marathon Championships in Cardiff, finishing just behind Britain's double Olympic champion Mo Farah.

World record-holder Dennis Kimetto had been due to race but the Kenyan, who clocked 2:02:57 in Berlin 2014 and a Chicago course record 2:03:45 in 2013, pulled out of the event with a stress fracture.

Kenya’s Kiplagat, the world record-holder in the half-marathon with 65:09, heads the women's field on times with her 2:19:44 from the Berlin Marathon in 2011.

Just behind her with a PB of 2:19:50 from London in 2012 is her compatriot Edna Kiplagat, the 2011 and 2013 world champion.

Ethiopia’s Atsede Baysa is back to the race she won in 2010 and 2012, the latter in her PB of 2:22:03.

Britain's London 2012 Olympians Scott Overall and Freya Ross are also among those in action in Chicago.

Tatyana McFadden looks for her seventh Chicago wheelchair title, while Australia’s Kurt Fearnley, a five-time winner in the Windy City, and Switzerland's Paralympic champion Marcel Hug head the men’s line-up.