Oisin Murphy - a champion with the X factor and a string of big winners

Oisin Murphy's drug test failure will send shockwaves throughout racing.

It is not just that he is the reigning champion jockey and odds-on to retain the title after another highly successful season, but Murphy is a jockey with something of the X factor, a man with an engaging personality who could transcend racing in the way Frankie Dettori has done before him.

On his march to a first title last year, Murphy made time for interviews in seemingly every media outlet, each feature revealing him as a confident young man, keen to eschew platitudes and happy to engage with any subject no matter how personally embarrassing.