L'Ami Serge won for the first time since the French Champion Hurdle in June in the Betway Aintree Hurdle.
Having garnered something of a reputation for not putting everything into the finish of his races, he was ultimately impressive in beating Supasundae.
The race could not have been set up better for him, as Diakali set off at a rapid pace on his first run for Gary Moore.
Turning into the straight, Clyne had joined him and held an advantage for two furlongs, but approaching the final flight the leading players were mounting up.
Supasundae was first to challenge and while My Tent Or Yours began to fade, Dary Jacob brought L'Ami Serge with a race-winning move.
The 5-1 shot pulled three lengths clear, with Clyne sticking on for third.
Jacob said: "It was a very good performance. I was quite keen to come back to two and a half miles because it suits him well. He's tough and when he's on his A-game like that, he's a very, very talented horse."
Joint-owner Simon Munir said: "That was a wonderful ride by Daryl. He really produced him right on the line. He's got so much ability, but with age, comes wisdom. Holding him up has made all the difference."
The victory completed a Grade One treble on the first day of the meeting for Nicky Henderson, who was also on the mark with We Have A Dream and Might Bite.
Henderson said: "He's an enigma. They didn't go fast enough for him in the Stayers' (Hurdle, Cheltenham Festival).
"He does deserve one for all the names he has been called, but he does threaten to win races. You couldn't be confident what was going to happen when he got there going to the last like that, but he did win the French Champion Hurdle last year.
"He has been a bit of a star along the way. I should think he will go back to France."
He added: "He's still in the three-miler (Ryanair Stayers' Hurdle) on Saturday. I doubt it, but we'll see - we'll talk to the boys.
"He's had a good year. We're very lucky. We have a strong team of horses."
Of My Tent Or Yours, who finished fourth, Henderson said: "He's run a great race, too, on ground he would probably have hated. You'd have to be proud of him."
Anthony Bromley, racing manager to Munir and Isaac Souede, said: "Minty (David Minton) was at Seven Barrows last week and rang me up saying he had seen the most spectacular work he has seen with L'Aami Serge.
"He has always threatened to get a big win. He deserved a big win in England, as he won the French Champion Hurdle last year. That will be the main aim for the rest of the season."
Jessica Harrington said of Supasundae: "It was a great run. He met L'Ami Serge on a going day and Robert (Power) said there was no excuse.
"He jumped super and the ground was no excuse. He travelled well and was just beaten by a better horse on the day, simple as that.
"He'll go to Punchestown. He's in the three-mile race (Ladbrokes Champion Stayers Hurdle) and the Champion Hurdle. We'll wait and see which way we go."
Asked whether Supasundae could embark on a career over fences next season, the trainer added: "If you can find me a Galileo that's a good chaser I'll send him chasing! No, we'll stay hurdling.
"He's come a long way from last year to this year and if I can do a couple of little tweaks over the summer we might get another couple of pounds out of him."