The Richard Bandey-trained Diesel D'Allier was a previous winner around the Prestbury Park cross country course – striking gold in 2019 when trained in France by Emmanuel Clayeux.
Bought by Bandey earlier this year, the grey finished a promising third at Cheltenham's November meeting behind the reopposing pair of Back On The Lash and Singing Banjo.
A 6/1 shot to go two places better in the hands of Harry Bannister, Diesel D'Allier was delivered to challenge Christian Williams' Potters Corner after the final obstacle and set up a grandstand finish.
No quarter was given by either horse or jockey and they flashed by the post almost as one – but the judge confirmed Bandey's charge had triumphed by the narrowest of margins.
"It's just immense emotion – great for the team and the lovely owners," said Bandey.
"It's amazing for a small team like us. I'm over the moon.
"I bought the horse during the summer from Emmanuel Clayeux and I bought him under duress from the wife, who wasn't too keen for me to purchase him.
"I had faith I was going to sell him, but about a month before he ran here in November I still hadn't sold the horse, so there was a little bit of pressure from home.
"I put a syndicate together of local people and friends who we've known for a number of years. They all came on board for a fun horse to take us to Cheltenham.
"He's done what I said he'd do and what Emmanuel proved he could do. It's just wonderful."