Roi Des Francs claimed the scalp of highly-regarded stable companion Pont Alexandre in the Grade Two Woodlands Park 100 Club Novice Chase at Naas.
Pont Alexandre returned from a lengthy spell on the sidelines to make a sparkling debut over fences last month, and the 4-7 favourite cruised to the front when heading long-time leader Sub Lieutenant on the run to two out.
But Roi Des Francs (13-8) was going equally well and a slightly better leap at the last saw him away from the obstacle quicker. His proven stamina kicked in at that point and he battled on to a length-and-a-half victory in the hands of Bryan Cooper.
Roi Des Francs was having his third outing over fences and Mullins felt his extra experience probably told over Pont Alexandre.
"It was a good performance. He had the extra run and probably fitness was the thing there," said Mullins.
"He likes jumping and galloping and it worked out for him. He's improving. He'll be stuck in all the races at Cheltenham, the RSA and four-miler (National Hunt Chase)."
Of Pont Alexandre, Mullins added: "It was his second run back after a long break. He was very well in the parade ring beforehand which is not a great sign. He was maybe too well.
"He was there up until the last having gone toe to toe with the leader early on. It wasn't a bad run and they are two good horses. I think he'll improve more for the run."
