The 9-2 chance, with jockey Sam Twiston-Davies in the saddle, held off a challenge from 2014 runner-up Somersby to win by one and a quarter lengths, as Special Tiara came third.
Reigning champion Sire De Grugy finished fourth, while 2013 winner Sprinter Sacre was pulled up before the last in just his second run in 15 months following a heart scare.
“He should have been the favourite on form. I couldn’t see why the other two [Sprinter Sacre and Sire De Grugy] were ahead of him in the market,” said Nicholls. “It must’ve been sentiment.”
Three-time champion Flat jockey Frankie Dettori, who bred Dodging Bullets, added: “He was bred to win the Derby, but this is the second best. It’s the equivalent of the 100m final at the Olympics and what a horse.”
Nicky Henderson confirmed he will not be rushed into making any decision about Sprinter Sacre’s future after the nine-year-old weakened when coming off the home turn in fifth place. “I don’t think we can make any predictions. If there’s a switch we can find that gets rid of what is affecting him, who knows?”
Victory gave Nicholls and Twiston-Davies a double after Aux Petits Soins won the Coral Cup, while the former secured a treble when 25-1 chance Qualando won the Fred Winter Juvenile Handicap Hurdle. Don Poli gave trainer Willie Mullins a fifth win of the meeting in the RSA Chase.