Ongoing cancer treatment will keep Sir Henry Cecil at home when Frankel takes on just three rivals in the Sussex Stakes at at Goodwood on Wednesday.
The world’s highest-rated horse will be defending his title in the Group One mile (1600m) as he bids to extend his unbeaten record to 12.
“Unfortunately, I won’t be at Goodwood on Wednesday as I have been undergoing some treatment,” Cecil said on his website.
“Although I am able to train my horses, I’m not quite fit to go racing yet, but I hope to be fully recovered in the near future.
“Everything has gone as we could have wished with Frankel since the Queen Anne Stakes. We gave him an easy time immediately after Royal Ascot before bringing him back into fast work.
“He has pleased us with his work and is going to the Sussex Stakes in good shape. We are taking one race at a time with him and are hoping that he can extend his unbeaten record.”
Frankel’s main test looks likely to come from Godolphin’s Farhh, who has run such game races in defeat in the Prince of Wales’s Stakes and the Coral-Eclipse.
Richard Fahey’s Gabrial, who stepped up from handicap company to finish a close fifth in the St James’s Palace Stakes at Royal Ascot, is the only other runner.
The other runner is Frankel’s stablemate and pacemaker Bullet Train.
With Frankel around the 1-20 mark, Paddy Power have tried to revive interest in the race as a betting on the margin.
He can be backed at 7-2 to win by 10 lengths or more, 5-2 to win by eight or more or 4-5 to win by five lengths or more.
