The Champion Stakes at Ascot on Saturday will feature four of the world's top six turf horses and mark a fitting end to the remarkable career of Sir Henry Cecil's unbeaten four-year-old.
Opposition to Frankel includes last year's winner, Cirrus Des Aigles, and the talented colt Nathaniel.
The £1.3 million QIPCO Champion Stakes (4.05pm) is Europe's richest 10-furlong race with the confirmations also including Aidan O'Brien's progressive performer Declaration Of War and the French-trained filly Ridasiyna.
Frankel's pacemaker Bullet Train and Master Of Hounds complete the line up but, with the possibility of soft ground for the weekend, the unbeaten star is expected to face his toughest outing yet.
Frankel has not run on ground described as soft since his debut victory at Newmarket in August 2010.
"I do not mind if it is slightly on the soft side," said Cecil.
"If it is very heavy, you can be in no man's land. Soft ground will not bother him at all."
He added: "The adrenaline is going. We have got him so far unbeaten. I would like him to win at Ascot."
Jockey Tom Queally, who has ridden Frankel to every one of his previous 13 successes, is anticipating an historic day at Ascot, but admits he has yet to comprehend the enormity of the horse's accomplishments.
"He has been an amazing part of my career and my life," he said. "When you're that close to it all, it's hard to grasp.
"He is raised my profile. I probably will not understand it all until 10 years down the line. No other jockey will ever get to sit on anything half as good. I am very fortunate and privileged."
Meanwhile Excelebration, the second best miler in the world behind Frankel this year, has his opportunity to win the biggest prize of his career in the Queen Elizabeth II Stakes at 3.30pm.
Her Majesty The Queen will be at the course to cheer on her runner Carlton House.
The four-year-old, who finished third in the 2011 Epsom Derby, has made three appearances so far this season, the latest being fourth place in the Group 2 Summer Mile at Ascot on July 21.