Kieren Fallon, the six-times Champion Jockey and international racing icon, took part in a multimillion pound conspiracy to defraud the betting public, an Old Bailey jury was told yesterday.

He and five other defendants allegedly conspired to fix races so that fancied horses under their control would lose. Those in on the alleged scam netted huge sums on the internet betting exchange Betfair by backing the horses to fail.

Evidence from the prosecution included an exchange of text messages in which Mr Fallon allegedly told a co-conspirator that he was afraid of being found out. The message, shown to the jury, ended: “They are watching me.”

Mr Fallon, 42, is accused of conspiracy to defraud alongside two other jockeys, Fergal Lynch, 28, and Darren Williams, 27. They were allegedly instructed which races to lose by Miles Rodgers, 37, a big-time gambler, either directly or through intermediaries. Mr Rodgers is accused of masterminding a conspiracy in which he laid bets of more than £100,000 per race on horses to lose, also denies concealing the proceeds of crime.

Shaun Lynch, Fergal’s 37-year-old brother, and Philip Sherkle, 38, are accused of acting as intermediaries between Mr Rodgers and Mr Fallon. The defendants deny all the charges.

Jonathan Caplan, QC, opened the case by saying that the reputation of horseracing was at stake.

“The defendants . . . fixed the races to ensure that the horse in question lost,” he said. “The object was to wager large amounts on a particular horse to lose in each of 27 races while knowing that the jockey was prepared, if necessary, to cheat by stopping the horse.”

He said that Mr Rodgers made “lay bets” — wagers that a horse would lose — on Betfair, a betting exchange that allows customers to take bets from one another.

The jury will be asked to study races between December 2002 and August 2004 in which the jockeys allegedly adopted a variety of tactics to ensure that their horses underperformed.Mr Caplan said: “One example would be if the jockey deliberately rides into a wall of other horses so as to impede its path or progress. Or if the jockey misses the start deliberately by delaying taking off the horse’s hood.”

Mr Caplan said that Mr Rodgers bet a total of £2.12 million on the 27 races.

Mr Fallon, who rode in 17 of the “fixed” races, was not a successful conspirator, the Crown claimed, because he won five races that he was meant to lose. Mr Caplan said that the wins were mistakes that resulted in Mr Fallon making a net loss for the conspirators of £338,000. “When [Mr Fallon] unexpectedly won, and in consequence cost the conspirators sizeable sums of money, they clearly felt that this was contrary to this agreement with them and sometimes they took steps to deal with it.”

Jurors were taken through Mr Fallon’s race on Goodwood Spirit on August 14, 2004, in the 6.55pm at Goodwood. It is claimed he sent a text reading “6.55 no 4 n” which indicated he would lose. Mr Rodgers allegedly bet £116,738 and won £29,822 when the horse came in third.

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