Victoria Pendleton struck the first blow in the women's sprint competition, setting a new Olympic record in the flying 200m of 10.724 seconds.
The personal best put her at the top of the rankings, eight hundredths of a second faster than her main rival for gold, Anna Meares of Australia. Shuang Guo of China, who is on fine form here in London, was third, a quarter of a second slower than Pendleton.
Only Miriam Welte (Germany) has gone faster when she set the world record (10.643) at altitude in Colorado Springs this June. A record that was only confirmed a few days ago.
There may only be fractions of a second between the top two but it is a significant difference. In April Meares was faster by three tenths of a second when she set a new world record of 10.782. Pendleton admitted it was a huge margin and in a sense should have meant a walk over for Meares when the two raced against each other.
Despite Meares being in better condition at the world champs in April, Pendleton still got the better of the Australian in a gripping semi-final. She went on to win the sprint title, the ninth world title of her career.
Qualifying faster than Meares here in London will give Pendleton another confidence boost coming in to the competition after she won the keirin two days ago. The sprint is however the title she really wants. It will also be her last competitive outing as she quits the sport after the Games.
In her first match sprint she faces Ekaterina Gnidenko of Russia who was almost one second slower in qualifying. If all goes to form she should only meet Meares if and when they both get to the final. Seeing the two best female sprinters of a generation battle it out for the Olympic title would make for a perfect end to the track racing here in London.
Men's omnium shaping up nicely
Ed Clancy was also in action on Sunday morning. He posted the second fastest time in the individual pursuit behind Dane Lasse Hansen, the fourth round of the omnium. The pair sit in equal second, just two points behind reigning world champion Glenn O'Shea of Australia with just two events to go.
The overnight leader Bryan Coquard of France was only 12th fastest in the pursuit and so dropped down to fifth. With only the scratch race and kilometre to go, just seven points separate the top six. Every rider will expect Ed Clancy to win the kilometre, the final event, making for a very difficult scratch race.
The Briton will have to mark O'Shea and Hansen, and expect them to mark Elia Viviani (Italy), Coquard and Roger Kluge (Germany). Baring disaster in the scratch race, the Brit looks good for a medal. What colour that will be is anyone's guess.
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