A maximum of seven rivals will take on Frankel as he tries to bid for a glorious farewell with victory in Saturday's Qipco Champion Stakes at Ascot.

Henry Cecil's colt is unbeaten in 13 starts and is almost certain to be retired to stud after this weekend.

Having proved his stamina in the Juddmonte International over 10 furlongs at York in August, the main worry for his connections this week is likely to be the forecast wet weather.

Frankel took part in a public gallop last week and looked stunning when pulling some 15 lengths clear of stablemate Midsummer Sun.

Pacemaking duties on Saturday are again likely to be taken up by Bullet Train.

"He's been good over the weekend, Henry is very pleased with him," Teddy Grimthorpe, racing manager to owner Khalid Abdullah, told At The Races.

"He came out of his workout well and on Saturday he did a bit up Long Hill.

"We're very pleased with him and it's all systems go.

"This is his biggest test to date - it's building up to be a real test for him."

Cirrus Des Aigles and Nathaniel appear Frankel's main rivals.

Cirrus Des Aigles won the race 12 months ago and although Corine Barande-Barbe's stable star has had an interrupted season, he showed his current wellbeing when winning the Prix Dollar at the Arc meeting by nine lengths.

John Gosden's Nathaniel was denied a run in the Prix de l'Arc de Triomphe due to a late setback but is on course to line up here.

The Galileo colt finished a half-length second to Frankel when the pair made their respective racecourse debuts at Newmarket in August 2010 - the closest any horse has got to Cecil's runner.

Aidan O'Brien's Declaration Of War has won two of his three starts since joining the Ballydoyle ranks from Jean-Claude Rouget and could make a massive leap in class.

The William Haggas-trained Master Of Hounds, Mario Hofer's German raider Pastorius and the Mikel Delzangles-trained Ridasiyna complete the list of possibles.