It had been a frustrating first two days to the meeting for Mullins, who hit the crossbar a few times and was forced to rule Chacun Pour Soi out of the Queen Mother Champion Chase on the morning of the race.
Paul Townend, riding as first choice jockey for Mullins in his own right for the first time this season, was also suffering, but he gave Ferny Hollow (11-1) a nerveless ride having been last in the early stages.
He met trouble in running coming down the hill as Patrick Mullins moved stablemate and favourite Appreciate It into the box position, but the market leader had no answer as Ferny Hollow powered home to win by two and a half lengths.
Mullins has now won the race 10 times, having struck first in 1996 with Wither or Which, a horse he rode himself.
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