French Derby winner The Grey Gatsby has been ruled out of the Champion Stakes at Ascot due to the expected wet ground.

The Kevin Ryan-trained three-year-old has enjoyed a tremendous campaign, winning the Dante Stakes at York, the French Derby and most recently lowering the colours of Australia in the Irish Champion Stakes at Leopardstown.

The son of Mastercraftsman was due to round off his season on Champions Day this weekend, but with testing conditions increasingly likely to prevail, Ryan has decided to draw stumps for the year.

"I'm not going to run him on heavy ground. They had 25 millimetres of rain last night and there is more forecast," Ryan said.

"He's done everything we've asked of him this year.

"He stays in training next season, so we'll look forward to that now."

French star Cirrus Des Aigles, who won the race in 2011, remains the favourite to regain his crown after having filled the runner-up spot behind Frankel and Farhh the past two years.

Aidan O'Brien has three remaining contenders in Kingsbarns, Ruler Of The World and Kingfisher, while fellow Irish trainer Dermot Weld is set to saddle a major player in Free Eagle.

Frankel's brother Noble Mission has enjoyed an excellent campaign and is in the mix for Lady Cecil.

Al Kazeem, Sheikhzayedroad, Ayrad and Western Hymn are also engaged, while the Richard Hannon-trained Pether's Moon is a late entry.