Nico de Boinville insists everything possible has been done to prevent Shishkin from downing tools again in the Ladbrokes King George VI Chase, but ultimately it will be up to the horse himself to behave at Kempton.

The nine-year-old has been a marvellous servant for Seven Barrows handler Nicky Henderson, winning 13 times under rules and claiming multiple Grade One victories.

However, he blotted his copybook when refusing to race in the 1965 Chase at Ascot last month and has been denied the chance to get back on track since that mishap.

A potential run in the Rehearsal Chase at Newcastle was ruled out due to that meeting being called off, while heavy ground at Sandown was considered unsuitable for the rescheduled Fighting Fifth Hurdle.

Shishkin must now go into the King George on Boxing Day with big questions to answer and De Boinville admits all his connections can do is work hard and hope for the best.

When asked how much can be done to get Shishkin going if he stalls again when the tape goes up, the jockey told Sky Sports Racing: “Not much – if horses don’t want to run, they won’t run!”

De Boinville, who has been ever-present in the saddle throughout Shishkin’s career, is happy with how his preparations have gone back in Lambourn, though.

“I’ve done lots of sitting on him,” he added. “All boxes are ticked and crossed and we’ve tried everything, so we won’t be going to Kempton thinking ‘oh, I wish we’d done that in practice’.

“It’s one of those, if he doesn’t want to do it, he won’t do it – no matter what I do.

“In actual fact, he’s one of those horses that the more pressure you put on him, the more he’ll dig his heels in.

“But look, he hasn’t shown one inkling of doing it since he’s got back home after Ascot.

“It would have been nice to have got a run into him, but these things happen and I’m looking forward to it – if we jump off and everything, I think he’s in for a big race.”