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Mark Chapman presents live Olympic coverage on a key day for Great Britain's rowers with commentary from John Murray and Olympic and world champion Mark Hunter at Lake Lagoa. Helen Glover and Heather Stanning, the World and Olympic champions and unbeaten since 2011, aim to retain their title in the women's pair at 2.30pm.

It's the first morning of the athletics competition as Jessica Ennis-Hill starts her defence of her Olympic heptathlon title, and David Rudisha goes in the heats of the men's 800m. And Jo Pavey also competes in her 5th Olympic Games in the women's 10000m.