Tao Geoghegan Hart has become the fifth Briton to win a Grand Tour with victory in the Giro d'Italia.
The 25-year-old Londoner beat Australian Jai Hindley by 39 seconds in the 15.7-kilometre closing time trial in Milan after the pair went into the final stage level on time.
Geoghegan Hart was ahead of Hindley at every time check along the way, clocking a time of 18 minutes 19.40 seconds to deliver a remarkable win.
His Ineos Grenadiers team-mate Filippo Ganna took the stage win with a time of 17 minutes 16.55 seconds, 32 seconds faster than second-placed Victor Campernaerts, to deliver his fourth stage win of the race and a seventh for the team.
Geoghegan Hart follows Sir Bradley Wiggins, Chris Froome, Geraint Thomas and Simon Yates in winning one of the big three stage races on the calendar, delivering Britain's 11th Grand Tour victory since Wiggins won the Tour de France in 2012, and second in the Giro after Froome in 2018.
But this was by far the most unexpected entry on the list, with Geoghegan Hart having started the Giro planning to support Thomas before the Welshman's race-ending crash on stage three.
An outstanding final week in the mountains propelled Geoghegan Hart up the standings, with his victory on Saturday's stage 20 setting up the unprecedented scenario of the top two in a Grand Tour being level on time at the start of the final day.