Farhh belied a lack of race fitness with a sublime performance to take the Qipco Champion Stakes at Ascot in a thrilling finish to the feature race on Champions Day.
The injury-plagued five-year-old, trained by Saeed bin Suroor, won the Lockinge at Newbury back in May but yet another setback had kept him off the track until now.
Advertising the skills of his handler, Farhh needed to have stamina and courage in equal fashion but his Brazilian jockey Silvestre de Sousa kept him up to his work to hold off the 2011 winner Cirrus Des Aigles by a neck as he bookended the season with another Group One win.
Ruler Of The World, the Epsom Derby winner, was another half a length away in third.
De Sousa said: "He travelled like a dream, and like the winner, through the race.
"He's a marvellous horse and I'm delighted."
Bin Suroor said: "He's a great fighter - every year he has had problems.
"He's a great horse and I'm so happy."
Both the first and second had been no match for Frankel last year but with one champion retired to stud, the space was there for another star to emerge.
Cirrus Des Aigles ran an amazing race for a seven-year-old and Ruler Of The World ran his best ever race after disappointing in the Arc two weeks ago.
Of the rest, Hillstar ran too keen early on, while Mukhadram, employing different tactics after being dropped out, stayed on one-paced to finish fifth, with Hunter's Light fourth.
Bin Suroor confirmed Farhh will now be retired to stud.
He said: "He had to have a break after winning the Lockinge. He's been a miler in the past but he did it today really well over 10 furlongs, especially in that ground.
"He'd been on good to soft but it was heavy today.
"You have to look after him really well just to keep him sound. It wasn't really easy to train him, if you put any pressure on you know what will happen. He looked the best ever today and he ran his greatest race.
"He is a great horse and I'm so happy.
"He'll be retired now and he'll go to stud."
Trainer Corine Barande-Barbe said of the runner-up: "He's run a very good race, having come back for the third year in a row.
"But I felt because of his bad draw it meant he couldn't get out before Farhh, who had a bit of a start on him and you can't afford that against a horse like him.
"I hope he has silenced the doubters who have criticised him this year and hopefully he will come back next year.
"I don't know if he'll run again this year, it's up to the owners."
Aidan O'Brien said of Ruler Of The World: "He has run a tremendous race against older horses and he's another horse to look forward to next year over 10 furlongs or a mile and a half."