Already a dual Cheltenham Festival winner in the Albert Bartlett and last season in the RSA Chase, his three-and-a-quarter-length defeat of top-weight Tidal Bay means Bobs Worth, ridden to victory by Barry Geraghty, is now available at no bigger than 5-1 to take the Gold Cup next March.
Surprisingly, in a big field not short of jumping mistakes and fallers, very few featured prominently and Irish raider First Lieutenant, who had pushed Bobs Worth all the way home in the RSA, was quickly into the lead and still travelling well in the home straight.
The 4-1 favourite, once owned by Geraghty, was not really spotted until the turn for home, prompting Bryan Cooper to conjure a phenomenal leap from First Lieutenant at the third-last.
It was not enough, and in spite of warnings at the start of the week from trainer Nicky Henderson over the dangers of potentially soft ground, Bobs Worth drew relentlessly clear as Tidal Bay stole second from the weakening First Lieutenant.
"He was potentially the classiest horse in the race and if he's going to get to the top, he had to win here," said Henderson, whose only other Hennessy triumph came from a similar type of horse in Trabolgan.
"He's so tough, but he makes you sweat as he doesn't do an awful lot. It was only three days ago when I went round evening stables that I thought he was right – it was like a rose coming into bloom. He's owned by some of my oldest friends, and it's for them and Barry more than anything."
Henderson recently mentioned the Lexus Chase at Christmas as an option for Bobs Worth and his main aim will be to keep the seven-year-old apart from stablemate Long Run.
"Barry has said before that he does need to go left-handed," he said. "So I would say the King George is out of the equation and it's just a matter of plotting a gentle route back to Cheltenham. We've been getting a lot of seconds this week, but then good old Bob comes to the rescue."
Geraghty said: "He's not overly big and you can't ask too much during the race. You just have to let him build and build. I was under the collar a lot of the way, but I knew going to the last I had plenty of horse.
"He has a very good pedigree of Jim Bolger's and I bought him as a yearling with my brother. He was not far from the top there. He loves loves it round here."
Meanwhile, Big Buck's continued to demolish all before him in taking his winning run to a staggering 18 with an effortless victory in the Sportingbet Long Distance Hurdle. The Paul Nicholls-trained nine-year-old, ridden by Ruby Walsh, was hardly out of a hack canter as he took this race for the fourth successive year.
Nicholls said: "That will put him right for the Grade One at Ascot in three weeks' time [Long Walk Hurdle]. I think he looks better than he did at any stage last year. Everyone will probably keep away until Cheltenham, but we'll keep ticking away with him winning these races. He's a real professional now and it makes my life easier."