Odds-on favourite Kauto Star could finish only third behind Long Run in his bid to win a record fifth successive King George VI Chase at Kempton Park on Saturday.
The 4/7 11-year-old favourite was under pressure coming into the home straight under champion jockey Tony McCoy and a serious blunder at the penultimate fence cost him any chance of overhauling 9/2 shot Long Run.
Long Run, given a dream ride by young amateur Sam Waley-Cohen, jumped the last in style to run away with the prize .
Had Kauto Star prevailed he would have been the first horse to win a major chase on five successive occasions since Golden Miller won five Cheltenham Gold Cups from 1932-36.