Victoria Pendleton was relegated by officials as Australia's Anna Meares took a 1-0 lead in the women's Olympic sprint final at the London 2012 velodrome.
After watching Laura Trott become a double Olympic champion with victory in the omnium, Pendleton met perennial rival Meares in the final in a repeat of the 2008 gold medal race which the Briton won.
The 31-year-old was aiming to finish her career on a high with a third Olympic gold - a record for a British female - and her superior pace saw her just cross the line first. However, Pendleton strayed from the sprinting lane under supreme pressure from the physical Meares and commissaires awarded the Australian victory in the first bout of the best-of-three final.