Best Mate made history on Thursday when he galloped to a third consecutive Gold Cup victory at Cheltenham.
The nine-year-old, who is trained by Henrietta Knight, joined an elite list of horses to have claimed the honour.
The last to achieve the treble was the legendary Arkle, who won the first of his three Gold Cups in 1964.
Best Mate, ridden by Jim Culloty, finished just ahead of second-placed Sir Rembrandt and third-placed Harbour Pilot in a tight finish.
Culloty admitted he was relieved to have passed the post first on what will be remembered as one of racing's greatest days.
"It was a nightmare," he told BBC Sport. "I walked the course beforehand and the best ground was on the inside.
"I didn't get the cleanest run but it worked in the end, thank God."
Culloty enjoyed an armchair ride on the champion as he pinged every fence up the inside rail as French raider First Gold blazed a trail up front under Thierry Doumen.
Best Mate looked to be cantering turning for home, but was very short of room and was squeezed up as the race started in earnest.
He jumped to the front two from home but Harbour Pilot, third last year, would not go away and looked for a
moment as if he might peg back the 8-11 favourite.
Best Mate: 2002-04
Cottage Rake: 1948-50
Golden Miller 1932-36
Sir Rembrandt found more for Andrew Thornton as well and it was a battle royal at the last but Best Mate held out to claim his place in racing history.
A jubilant Ms Knight added: "I thought we were beaten coming to the last, but he's tough, too. He was brilliantly ridden."
Owner Jim Lewis paid tribute to his team and the longevity of his horse.
"I really was ready to lose because the dream has to come to an end one day," he said.
"It was tight in the end, but it's not the greatest ground for him. What we saw today is that he is an amazing jumper."
Sir Rembrandt's jockey Andrew Thornton said: "I gave the last just a bit too much daylight.
"I met the fence on a long, long stride and he just came up for me.
"I never really got there. It was a length and a half, then it was a length, then it was half a length, but he just had a tendency to drift to his right."
"I said all along that he was back to his best."