Bookmakers are bracing themselves for Kieren Fallon fever when the former champion jockey makes his eagerly-awaited return tomorrow.

The 44-year-old last rode in Britain in July 2006 due to a combination of the Old Bailey trial into alleged race-fixing, which ended in the judge ruling there was no case to answer, and an 18-month drugs suspension.

But while Fallon's comeback will keep the turnstiles clicking at Lingfield and Kempton, where he splits seven rides, bookmakers are nervous.

"Having been champion jockey six times and won 15 British Classics, Fallon obviously has a huge following," said Coral spokesman David Stevens.

"We expect all his mounts to be extremely well backed. Were he to win all seven races, we would face the biggest payout since Frankie Dettori's 'magnificent seven' at Ascot 13 years ago."

Betfred offer 500,000-1 Fallon wins on all seven, 5-1 that the Irishman picks up a ban and 7-4 he draws a blank.

Meanwhile, Aidan O'Brien warned that Rip Van Winkle's on-going foot problems mean that the colt is "touch and go" to make the Queen Elizabeth II Stakes at Ascot on 26 September, but Aqlaam could spearhead the British challenge in Sunday's Prix du Moulin at Longchamp.

The William Haggas-trained colt is one of 13 left in France's top mile event.

John Oxx is likely to rule Sea The Stars out of Saturday's Group 1 Irish Champion Stakes at Leopardstown later today because of soft ground.