Sifan Hassan, the Dutch athlete who became an Olympic champion in both the 5,000m and 10,000m events, made a remarkable debut in the London Marathon, emerging as a surprise winner despite injury and near-accidents. Hassan gave a masterclass in breaking every rule in the marathon book, stopping twice to stretch an injured hip and almost pulling out. In the men’s race, Kelvin Kiptum, a 23-year-old Kenyan, put up a remarkable performance, surging powerfully ahead with eight miles to go and leaving behind some of the fastest men in history.