Un De Sceaux stretched his unbeaten record to nine with another superb front-running victory in the Prix Leon Rambaud at Auteuil.
The dual French bumper winner has made a huge impression since making his debut for champion trainer Willie Mullins in February of last year, barely coming off the bridle in his first five starts over hurdles in Ireland.
The six-year-old returned to his homeland to clinch the Prix Hypothese at the end of March, just holding the late thrust of French star Gemix, and the two locked horns again at Grade Two level in Paris.
With stable jockey Ruby Walsh making his comeback from the injuries he suffered at the Cheltenham Festival, Un De Sceaux soon adopted his customary front-running role, albeit slightly more restrained than has been the case in the past.
He began to draw clear heading out onto the second circuit, jumping fluently throughout, but by the time he straightened up for home, the chasing pack had closed the gap.
Saint Du Chenet was the first to challenge, with Gemix waiting in the wings, but Un De Sceaux skipped over the final flight and stayed on for pressure to take the prize with something to spare.
Le Grand Luce finished strongly to grab the runner-up spot, with Saint Du Chenet third and Gemix back in fourth.
Mullins is unsure whether Un De Sceaux will run again before being given a summer break.
He said: "It was a good performance as the ground is very testing and he was staying on well at the end.
"I don't have anything else in mind for him at this stage, but we'll have a look at the French calendar when we get home.
"I don't think there is anything in Ireland or England for him, so if he is to run again it will probably be in France.
"He doesn't need another run. He's had a great season already and we're not particularly anxious to run him again - unless an opportunity presents itself."
The champion trainer is similarly in no rush to decide on plans for next season with his exciting youngster, who could remain over hurdles or begin a career over fences.
"That is another day's work and something we'll have a look at later," said Mullins.
"For the moment we'll enjoy today and another good win for the horse."