The 45-year-old, who is riding in his fourth Olympics, scored 77.72 per cent on Uthopia, comfortably the highest score of the opening seven-rider session at Greenwich Park.

‘I am very happy – it felt like a very good performance,’ Hester said.

‘I know it’s not the highest mark I’ve had, but I have to take into account it is the Olympics, it is the toughest judges, it is the toughest standard and I am in the first group of competitors.

‘I had one obvious mistake, which took me down to under 78 per cent, which would have been my ideal score, but 77 per cent is still great. The horse felt good.’

Britain are the reigning European team champions, and their trio of Hester, Laura Bechtolsheimer and Charlotte Dujardin have an outstanding chance of Olympic gold.

Bechtolsheimer is the second British rider in action, while Dujardin’s Grand Prix test is tomorrow afternoon.

Team scores from the Grand Prix are combined with those in next Tuesday’s Grand Prix Special to decide the Dressage Team medallists, with Britain expected to face stiff competition from Germany and Netherlands.

For complete results from Day 1 of dressage and tomorrow’s schedule of riders click here.

Photo Courtesy of London 2012 – Carl Hester and Uthopia