Swiss cyclist Marlen Reusser retained her world time-trial title in Montreal on Sunday as her main rival Demi Vollering finished a disappointing eighth.
Time-trial queen Reusser celebrated her 35th birthday with an ultimately comfortable victory, but not before Briton Zoe Backstedt gave her a scare.
Backstedt had been quickest at the first two intermediate time checks on the 39.2km course, but Reusser powered away in the second half of the race to beat the 21-year-old by 40 seconds, with German Franziska Koch finishing third, a further six seconds back.
Double world champion Reusser has been virtually unbeatable in races against the clock in the last few years.
She is a four-time European champion and has won time-trial stages at the Tour de France Femmes and Giro d'Italia Women.
Backstedt had been a junior and twice under-23 world champion in the discipline, but this race was around 12km further than any previous time trial she had competed in.
Koch's bronze medal continued a dream season for the German, who won Paris-Roubaix in April.
Vollering, the European road race champion, was never in the running for a medal.