The eight-year-old was pulled up by David Bass midway through the extended two-and-a-half-mile contest which was won by the Nicky Henderson-trained Champ.
After making a winning debut at Huntingdon, the Kalanisi gelding added a further six victories to his name, including the Grade Two Aintree Bumper and the 2015 Challow Hurdle at Newbury.
Pauling said: “He looked great for a circuit, then it just didn’t happen. He has been a horse that won his first seven, won me my first Grade One, my first Listed race, Grade Two and really put me on the map.
“There is nothing else he could have done for me. I’m not going to continue to run him when he is not right. He had worked really well at home, but today it didn’t work and that is that.
“He will be a very sad horse to let go from the yard, but one I am exceptionally proud of. He will be a riding horse for someone, but I don’t think he will be going very far.”