THE market did not act rationally in shortening Blaklion’s odds for the Grand National on the back of his Becher Chase win at Aintree last Saturday. Paradoxically perhaps, Nigel Twiston-Davies’ horse’s chances of winning the Aintree Grand National were probably reduced on the back of Saturday’s win, not enhanced.

Bookmakers love to shorten a winner. Regardless of how impressive or otherwise a horse is in victory, or no matter how little he achieves, a win usually results in the tightening of the odds on any potential ante post target that the horse may have.