Great Britain's Christine Ohuruogu advanced through to the semi-finals of the women's 400m this evening.
The 28-year-old ran well down the back straight, leaving her in contention for a qualification place coming into the final 100m.
She held off the challenge from Jamaica's Rosemarie Whyte to finish second in a time of 50.22.
America's Sanya Richards-Ross won the race in a time of 50.20.
