The champion jockey was poised to return to the saddle at Newmarket on Friday, but his injury worsened while on holiday in Sardinia.
"Frankie aggravated the injury swimming which has put his recovery back for about three weeks," explained Dettori's agent, Ray Cochrane.
"He would return to racing today if he could, but he will be taking things steady for a while. He's a bit down and the shoulder is very sore. He probably overdid it a bit but he's as determined as ever to get back."
The setback means Dettori will now miss the ride on Dubawi when he tackles the unbeaten Divine Proportions in Sunday's Prix Jacques le Marois at Deauville.
Attraction, one of last year's three-year-old stars, is scheduled to make her belated British four-year-old debut in Saturday's Hungerford Stakes at Newbury.
Mark Johnston's charge won four top-level prizes last term; after becoming the first horse to take both the Newmarket and Curragh 1,000 Guineas, she added the Coronation Stakes at Royal Ascot and the Sun Chariot Stakes in October. But she has not been seen since disappointing in the Champions Mile in Hong Kong in May.
"She had a fetlock injury which she took a while to get over," said Johnston yesterday. "That has disrupted a lot of her season; she wasn't ready for the Falmouth Stakes at Newmarket last month and the ground went too soft when we'd hoped to run her in France. She's in good shape now and we'll be delighted to get another run on British soil under her belt."
Attraction, who endeared herself to the public with her from-the-front courage, her wonky forelegs and windmill galloping action, will have to shoulder a Group One penalty in the Group Three seven-furlong contest, which has attracted 24 entries, including the progressive handicapper New Seeker and the Golden Jubilee Stakes runner-up Galeota, winner of the Mill Reef Stakes on the track last year.
The Group Two feature on Saturday's Newbury card, the Geoffrey Freer Stakes, hast 10 entries, but the star among them, Mubtaker, is not a certain runner. The eight-year-old has won the race for the past three years, but has an alternative engagement at Newmarket on Friday.
"He has to carry a penalty this year," said his trainer, Marcus Tregoning, "and it looks a better race than usual. But we'll see."Reuse content