Victoria Pendleton has won everything there is to win in women's track cycling, but it will all count for nothing if she does not deliver gold at her home Olympics.
The 31-year-old claimed four world sprint titles in a row and five out of six between 2005 and 2010, and also won the Olympic sprint title in 2008.
However, despite already being one of Britain's greatest ever track cyclists, Pendleton has said success at London 2012 is "the only goal that's ever going to matter". Fortunately, Pendleton is an expert at fulfilling expectations.
In Beijing she had to sit and wait while the likes of Sir Chris Hoy, Bradley Wiggins and Rebecca Romero claimed gold after gold, leaving her with the public expectation of rounding off Britain's winning run.
However, she displayed a cool head as well as a fierce competitive streak to deliver the perfect finale for Team GB's cyclists by beating her perennial rival, Australia's Anna Meares, in the final of the individual sprint.
Pendleton has revealed glimpses of vulnerability at times. In 2010 she raised the prospect of retiring from the sport and a defeat by Lithuanian rider Simona Krupeckaite at last year's European Championships left her in tears. Typically, though, she bounced back to win the keirin after her setback.
At London 2012 the pressure will come on three fronts, as she competes in the sprint, keirin and team sprint, rather than just the one event she tried for at the Beijing Olympics.
However, Pendleton's record shows that she is more likely to deliver when the challenge is greater.