Oxfordshire's Irish Olympian Aoife Clark held her nerve under intense pressure to win the Fidelity Blenheim Palace International Horse Trials yesterday.

Clark, who is based in Middle Barton, just eight miles from the scene of her first CCI three-star triumph, posted a clear showjumping round after closest challengers Jean Teulere and Clark Montgomery left no room for manoeuvre.

Frenchman Teulere and American Montgomery both finished on their cross-country scores of 45.5 penalties, which meant that Clark could not afford a mistake aboard nine-year-old chestnut mare Fenyas Elegance.

And Clark did not disappoint, remaining on 44.0 penalties to take the £8,000 winner’s purse and a title that numbers Zara Phillips, Mary King, Pippa Funnell and current world No 1 Andrew Nicholson among its former holders.

Teulere, eventing world champion 11 years ago, secured the runners-up spot on Matelot Du Grand Val because he finished closer to the cross-country optimum time of ten minutes ten seconds than Montgomery, riding Loughan Glen.

Sussex-based Gemma Tattersall was the highest British finisher in fourth spot on Arctic Soul, which again underlined her promise as a potential contender for the Rio 2016 Olympics. She is currently part of British equestrian’s world-class performance programme.

Clark, who rode Master Crusoe to seventh place at London 2012, conquered Blenheim just two hours after the Irish eventing team were crowned European junior champions in France.

“I knew I had to go clear,” Clark said. “We’ve only had one show-jumping rail down all year, but there was still pressure.

“To win here means a huge amount. This mare is just at the right stage to be looking at the (2014) World Equestrian Games and then Rio.”

Clark was second with Fenyas Elegance at Chatsworth International in Derbyshire earlier this year, and then eighth in the British Open, and she added: “The horse was such a star this week.

“We knew she was in great form and peaking, but I couldn’t have asked for any more from her. I will go home now and crack open some bubbly!”

Owen Moore, who is based at Lyneham, near Chipping Norton, finished 26th on Perfect Stranger.

Ginny Howe, based at Murcott, was 42nd on Eires Rock, while Kingston Bagpuize rider Charlotte Agnew, on Out Of Africa Two, withdrew. British star William Fox-Pitt, formerly based at Tackley, near Kidlington, meanwhile, continued a rapid rate of progress with Fernhill Pimms by landing the prestigious CIC three-star eight and nine-year-old class.

Only six weeks after winning the British Intermediate title at Gatcombe, the combination proved too strong for a star-studded field.

Fox-Pitt collected just 0.4 time faults around Eric Winter’s cross-country course to finish on a score of 33.5 penalties.

The world No 2 was left with little margin for error after Australian Christopher Burton jumped the competition’s solitary clear round inside the time aboard Graf Liberty.

But Burton had to settle for second spot with 36.9 penalties, well clear of New Zealand’s twice Olympic individual gold medallist Mark Todd in third, while Australians Bill Levett and Paul Tapner finished fourth and fifth, respectively.

Fox-Pitt’s victory ensured a weekend of mixed fortunes ended on a high note. He had a heavy fall from Before Time during Saturday’s CCI cross-country phase, and then he retired his second ride Running Order following a run-out.

And after going into the CIC showjumping phase aboard Freddie Mac in third place, he was eliminated for contravening a Federation Equestre International rule on the style of hind-leg boots allowed in a young horse championship.