Theo is involved as an ambassador for the event's official charity – the Willow Foundation which provides special days for seriously ill 16 to 40 year olds.

The England international took time out of his training schedule to be pictured with Hugo The Hound, Gunnersaurus and Sedge The Field Mouse who will be among the competitors in this year's race on Sunday, October 5.

With the race reaching its 10th anniversary, the racecourse is aiming to attract more than 100 mascots to take part in the madcap event which gains a worldwide television and online audience for the crazy antics of the participants.

The Willow Foundation, founded by former Arsenal goalkeeper Bob Wilson OBE and his wife Megs after their daughter died of cancer aged 31, will be the beneficiary of fund raising around the John Smith's Mascot Grand National.

Theo said: "The Willow Foundation helps people my age so what they do really means something to me. The Arsenal connection and the opportunity to work with a legend like Bob Wilson make it extra special. I'm pleased to be helping make more special days possible."

The Mascot Grand National – sponsored by John Smith's, the sponsors of the actual Grand National - is the highlight of every year for Britain's mascots.

Mascots the length and breadth of the country step up their training as they prepare for the big day.

It's a hilarious occasion when upwards of 70 mascots run, walk, stagger and stumble over obstacles on a gruelling one-furlong – 220 yards - course.

There's been mayhem, controversy, accusations of gamesmanship, and claims of 'ringers' over the years since this madcap race began in 1999, but strict rules now ensure good clean fun.

Managing director of Huntingdon Racecourse Sophie Hodgkinson said: "The John Smith's Mascot Grand National has grown in size and popularity year after year. We're targeting more than 100 runners this year for the 10th running of the race."

The John Smith's Mascot Grand National kicks off an afternoon of jump racing at the course.

>> RACECOURSE ADMISSION

Admission on Sunday, October 5: Main enclosure £15; picnic enclosure £8. Accompanied children under 16 – free.

Parking: free.

Times: Gates open at 12.10pm. John Smith's Mascot Grand National at 1.10pm. First horse race 2.10pm.

Contact information: telephone 01480 453373 or email mascot.huntingdon@jockeyclubracecourses.com