Peace And Co gave trainer Nicky Henderson his sixth success in the JCB Triumph Hurdle at Cheltenham after a hard-fought battle with stable companions Top Notch and Hargam.
Barry Geraghty rode a patient race on the 2-1 favourite, as Dicosimo made the running before finding his way to the near side rail to make his challenge on the run to the final flight.
He was soon on the heels of his two stablemates at the last and it quickly developed into a duel between the two principals, owned by Simon Munir and Isaac Souede.
Peace And Co, a winner on the course in January, powered up the hill to land the spoils by a neck from Top Notch, with Hargam and Tony McCoy four lengths away in third.
Geraghty said: "He's a lovely horse, he travels well and jumps. The ground was hard work and it probably killed his speed, but I could afford to sit and wait and I knew the longer I waited the better his chance.
"As the rain fell I knew the gap between him and Top Notch would shorten, but I always felt this fella had that little kick to do it.
"The ground is soft, it's not desperate and where it's fresh it's not too bad."
Henderson said: "They had to come here and do that, but it's a bit of bad luck that you have to go beating up your own troops.
"Peace And Co would jump fences if he had to, but I don't suppose we'll be doing that for a while."