SIR Chris Hoy stands on the threshold of becoming Britain's greatest ever Olympian with the country on the brink of history today as the host nation looked set to make the London 2012 Games its most successful in more than 100 years.

Hopes are high Team GB will equal or surpass the 19 gold medals won at Beijing 2008.

The Edinburgh-born cyclist will eclipse the five Olympic golds won by rower Sir Steve Redgrave if he retains his title in today's keirin event.

The 36-year-old matched Redgrave's tally on Thursday when he led the sprint team to victory, but afterwards played down his success.

Hoy described last week's achievement as "amazing, but it's just a number". He added at the time that he didn't think that anybody could better Redgrave's medal haul.

"It's not just the number, it's the way he did it and the fact it's five consecutive Games."

A medal of any colour will see Hoy top the British Olympic medal table by equalling fellow cyclist Bradley Wiggins's mark of seven, while also holding more golds than his counterpart.

On the last day of action in the Olympic Velodrome, two other Britons are going for gold as Team GB stands third overall with 40 medals – 18 gold, 11 silver and 11 bronze – behind China and the US.

Track queen Victoria Pendleton bows out from the sport today with a sprint finish as she bids to become Britain's most decorated female Olympian.

With one gold before the Games began, the 31-year-old from Stotfold, Bedfordshire, took the keirin title on Friday and is looking for a third in the sprint tonight to go one better than Dame Kelly Holmes and Rebecca Adlington before retiring.

Five-time Olympic champion Sir Chris will also be hoping to make it six in the keirin, an event which to many is something of a lottery but appears almost a formality for the Scot.

Sir Chris first became Olympic champion in Athens in 2004, with victory in the 1km time-trial, before claiming a hat-trick of victories in Beijing and the team sprint title on Thursday.

And 20-year-old world champion Laura Trott is top of the standings going into the final day of the omnium.

Elsewhere, fans will see brothers Alistair and Jonny Brownlee start as hot favourites for gold and silver in the triathlon as they swim, bike and run around Hyde Park and some of London's iconic sights.

Reigning world champion Alistair, from Horsforth, West Yorkshire, went into the Games as one of the host nation's best hopes for gold after dominating his sport for the last three years.