Jock started his show jumping career with John Pocklington where he broke and competed homebred young horses alongside Dermott Lennon. After two years he moved on to train and ride with Malcolm Pyrah, greatly benefiting from his training and guidance, and went on to win a national final and also competing at Horse Of The Year Show. Two years on he moved to Germany to ride for the Weinburgs. With 50 horses in the stables he had 15 horses to ride every day, from novices to Grade A's. The greatest success so far came for him at the Weinburgs where he won 'The Kreismeister Final'.

Two years later he moved back to England to ride for Robert Smith, where he trained for three years alongside Robert. He rode in his first Grand Prix and also jumped again at HOYS. After riding for Robert he decided to set up his own yard, where he is importing quality horses from the continent, and producing them ready for sale. He is also taking horses to compete for owners.

Julie Leonard aka Cilla, partners Jock in the business, having previously worked with horses for 15 years, starting for Paul Schockemohle where she was traveling groom to Otto Becker for 5 years. Afterwards she returned to England and worked as a traveling groom to Nick Skelton for 10 years.

The experience gained from her previous work has been invaluable to the set up of JM Sport horses. Now Jock has a lovely base in Claverdon, Warwickshire, which comprises of 15 stables, wash box with hot/cold water and heat lamps, tackroom, outdoor school with a good surface and an excellent set of show jumps, all set in 14 acres of grassland. Central to many major equestrian centres including Solihull, Weston Lawns and Stoneleigh.