Frankie Dettori spoke of his "honour" at being chosen to partner Camelot in the Prix de l'Arc de Triomphe at Longchamp on Sunday.
The ride on the 2000 Guineas and dual Derby winner became available as trainer Aidan O'Brien's son, Joseph, is unable to get down to the weight of 8st 11lb.
Dettori has not ridden for O'Brien since winning the 2005 St Leger at Doncaster on Scorpion.
The Italian will be riding in his 25th consecutive Arc, which he has won three times on Lammtarra (1995), Sakhee (2001) and Marienbard (2002).
"It's a real honour to be chosen to ride the Guineas and Derby winner in the Arc," Dettori told Racing UK.
"A couple of high-profile horses haven't made the race so he's right up there at the head of the betting.
"I'm really excited. It's a really good record, 25 Arcs in a row, so I'm looking forward to it.
"What has happened in the last few days is pretty unbelievable" - Frankie Dettori
"It's a shame this year that Godolphin don't have a horse in the race.
"What has happened in the last few days is pretty unbelievable (with defections from the race) - Snow Fairy has an injury, Nathaniel is out.
"Joseph can't do the weight on Camelot and the ride became available.
"It's an honour for me to be asked to ride the horse and I'm really looking forward to it.
"Let's hope the horse is in tip-top shape.
"It's been a long season but if the Camelot turns up we know he should have a really good chance."
Camelot's participation in the Arc had been up in the air since his defeat in the St Leger at Doncaster last month, when he was prevented from claiming the Triple Crown by Encke.
But after having worked at O'Brien's Ballydoyle stable on Wednesday morning, the decision was made to let the three-year-old colt take his chance.
"We were pleased with the work of both St Nicholas Abbey and Camelot in Ballydoyle and hope to run both in the Arc on Sunday," read a tweet from Ballydoyle.
"St Nicholas Abbey will be ridden by Joseph and Camelot will be ridden by Frankie Dettori."
Joseph O'Brien partnered Camelot in his key final Arc prep and said: "I was very happy with him - he did what he had to do."
Camelot adds a much-needed touch of quality to an Arc which has recently seen three high-profile withdrawals.
Injury forced Snow Fairy out of contention at the weekend, while last year's winner Danedream is unable to travel to France as her stables at Cologne racecourse were on Monday placed into quarantine due to a serious outbreak of an equine infection.
The John Gosden-trained Nathaniel was then declared a non-runner on Tuesday after returning unsatisfactory blood tests when found to have been suffering with a temperature.