Jump racing's showpiece Cheltenham Festival gets under way on Tuesday but the 2014 edition has a cloud hanging over it according to leading trainer Willie Mullins because of a doping case involving another Irish handler.

Philip Fenton, who will saddle Last Instalment, owned by Ryanair boss Michael O'Leary, in the blue riband Cheltenham Gold Cup on Friday, is facing a court case after anabolic steroids were allegedly found at his yard two years ago.

He strongly denies any wrongdoing.

He got a boost when his horses were cleared to run at Cheltenham last week by the British Horseracing Authority after it carried out emergency dope tests on his intended runners.

Mullins, who will send 40 horses to the Festival, is adamant that regardless of the outcome, the affair has had an impact.

"Lots of people have missed the fact that it has put a cloud over our game in the biggest festival of the year," Mullins told The Irish Times.

"That's what it will be known as - the year of the cloud.

"People in racing are in a bubble. We don't look out. But if this was another sport we would say 'Yeah, they're all at it'.

"We don't realise that people will be saying the same about us. There are so many other sports and things people can put their money into. So we have to mind our game."

One of those Mullins' stable stars, legendary hurdler Hurricane Fly will bid to get the meeting off to a great start with a third Champion Hurdle win on Tuesday.

If successful, the 10-year-old would extend his world record in Grade One races to 20 victories.

His main rivals look to be another Irish runner in Our Conor, who is half his age at five and won the Triumph Hurdle at the Festival last year in terrific style, and English duo My Tent or Yours and The New One.

However, Hurricane Fly got the better of Our Conor in the Irish Champion Hurdle in January while My Tent or Yours, trained by Nicky Henderson, suffered an injury scare last week and The New One is untried at this level.