Reigning Olympic marathon champion Sammy Wanjiru (picture), of Kenya, defended his men’s title and Russian Liliya Shobukhova made it back-to-back women’s titles at the Chicago Marathon yesterday. Wanjiru, 23, outraced Ethiopia’s Tsegaye Kebede in the final mile for the victory in an official time of 2:06.24, 43 seconds off last year’s course record, and 18 seconds ahead of Kebede. Shobukhova repeated as the women’s winner in 2:20:25, breaking the Russian national marathon record owned by training partner Galina Bogomolova by 22 seconds and putting her 10th on the all-time marathon list.