Isobel had to declare her competition intentions for 2013 to the governing body for horse sport, the FEI, by January.
Some had speculated that the 62-year-old might give up judging to compete abroad — with a view to vying for British team selection.
But Isobel, who is one of just three five-star judges in the UK, told H&H she did not think Chagall was ready for grand prix just yet. She was not prepared to give up judging to ride him internationally at a lower level.
“In the end, it was not a difficult decision,” she told H&H. “He has only done five inter I tests and is not established enough to go internationally at grand prix.
“I have seen enough horses come down the centre line that are not strong enough and I would not do that to my wonderful horse.”
Fellow top-level judge Stephen Clarke said: “It can’t have been an easy decision for Isobel as Chagall is a very good horse. But she and Andrew [Gardner] only became five-star judges last year, so it would have been a shame for her not to have judged this year.”
British Dressage chief executive Amanda Bond added: “We’re thrilled that Isobel is continuing her main focus on judging.
“It’s testament to her horsemanship that she’s giving Chagall the time to develop and not rushing him to the top.”
Isobel’s decision was perhaps prescient as the gelding has a slight cut and is currently confined to his box.
She also moved from Carl Hester’s yard in the autumn to avoid a conflict of interest with her judging.
This news story was first published in the current issue of H&H (17 January 2013)