Sire De Grugy ran out a six-length winner of the Queen Mother Champion Chase at the Cheltenham Festival.
Ridden by Jamie Moore, for his trainer father Gary, the eight-year-old eased to victory from runner-up Somersby with Module third.
The 11-4 favourite was given a rapturous reception in the winners' enclosure by supporters bearing the red and blue of owner Steve Preston.
Sizing Europe, a former winner and dual runner-up, ran well to finish fourth.
Second favourite Captain Conan, trained by Nicky Henderson, disappointed and was pulled up by jockey Barry Geraghty.
Sire De Grugy was securing his third Grade One win of a season where he has taken advantage of the absence of 2013 champion Sprinter Sacre.
Henderson's Sprinter Sacre won the Champion Chase by 19 lengths a year ago, but is out for the rest for the season after a heart scare.
Success for Sire De Grugy completes a remarkable story for the Preston family after father Steve bought the racehorse with help from his sons and friends to celebrate his 50th birthday.
Sire De Grugy has now won five out of his last six starts and ends his Cheltenham hoodoo where he finished second on each of his last two races on the Gloucestershire course.
"It's something I hoped would happen but it doesn't happen very often," said Moore Sr. "The plan worked out very well.
"The horse is professional and easy to train to a certain extent. He trod on a stone 10 days ago and it was a little worry but it couldn't have gone any better today. I was getting text messages from 6am this morning, wishing me good luck."
Captain Conan was tipped to be Sire De Grugy's closest challenger but never got going under Barry Geraghty, although he returned to the paddock unharmed.
Meanwhile Ruby Walsh started day two at Cheltenham just as he did the first as he rode Faugheen to a straightforward victory by around seven lengths in the Neptune Novices' Hurdle.
The Willie Mullins-trained six-year-old, the 6-4 favourite, cantered along before sprinting to the finish, comfortably beating second placed Ballyalton and Rathvinden in third.
There were two thrilling finishes in the RSA Chase and Coral Cup.
O'Faolains Boy pipped favourite Smad Place by a neck in the former to give Geraghty his second win this week, producing a thrilling performance to win from 12-1.
It was the Irishman's 30th win, overtaking AP McCoy into second place for all-time Festival wins.
McCoy's misfortune continued as his horse Get Me Out of Here finished runner-up for the fourth time at this meeting, beaten by Nico De Boinville on Whisper in a photo finish.
Photography had to decide the Handicap Chase as well, with 2012 Balthazar King, ridden by Richard Johnson, producing a brave performance to just get the better of Any Currency and last year's winner and 3-1 favourite Big Shu, who finished third.
Johnson hinted afterwards that Balthazar King could now be considered for next year's Grand National.
Hawk High, ridden by Brian Hughes, was a surprise winner at 33-1 for owner Trevor Hemmings and trainer Tim Easterby, winning by a length from Katgary in the Juvenile Handicap Hurdle.
In the final race of the day, Silver Concorde, ridden by Robbie McNamara, denied Walsh a fourth win of the week beating Shaneshill by a length and a half to claim victory in the Champion Bumper.