Three-time champion jockey Ryan Moore has returned to action at Ascot on Friday after recovering from a broken arm and thumb sooner than anticipated.
The 27-year-old was expected to be out for the season, which runs until 5 November, after suffering the injuries in a fall at Glorious Goodwood in July.
Moore finished fourth on Tuscania in the first race, the PWC Handicap.
On Sunday, Moore will attempt to win a second successive Prix de l'Arc de Triomphe on Workforce.
The Brighton rider also guided the Sir Michael Stoute trained Workforce to a course record-breaking victory in the Derby last year.
Moore, who won the jockeys' championship in 2006, 2008 and 2009, has also become a leading choice for Aidan O'Brien in the absence of a stable jockey at Ballydoyle.
However, his hopes of winning this year's crown were ended when his mount Verdant was brought down by Captain John Nixon on the final day of the Glorious Goodwood meeting at the end of July.
Jamie Spencer's horse Activate was also brought down but he escaped unharmed.