Ali v Frazier, Borg v McEnroe, Nicklaus v Watson, Federer v Nadal, Denman v Kauto Star -- spot the odd one out.
The answer is that there isn't one; whether horses or humans, these names evoke some of the great sporting duels of the past 40 years, and when the next chapter of the story of two remarkable stablemates unfolds at the Cheltenham Festival a week today, it will have an intriguing extra dimension: Tony McCoy v Ruby Walsh.
In next Friday's Gold Cup, according to the bookmakers, Walsh and Kauto Star will prevail. McCoy has only had one competitive ride on Denman, in the Aon Chase at Newbury last month, and it was a disaster, the champion jockey parting company with his formidable mount at the third-last.
This fuelled talk that the partnership of McCoy and Denman is doomed to fail. McCoy's style is to impose his will on a horse, they say, and Denman's style is to impose his will on a race. It is a meeting of the immovable object and the irresistible force.
One English commentator opined that McCoy would not be his first, second, third or even fourth choice to partner Denman.
The weighing room at Ludlow racecourse last week was a place for weighing jockeys, not insults, but it is there that McCoy, with the ghost of a smile, considers his critic's words. "Everyone gets criticism at some stage in their life," he says.
"As it happens, I'm my own greatest critic, but the opinions of some people I respect more than others. He is not John Francome, he's not Ruby Walsh. If I heard that they had criticised me, I'd go and ask what I was doing wrong. But this had no impact on me whatsoever."
McCoy, who has been British champion jockey in each of the last 14 seasons with more than 3,000 career winners, is not irked by the controversy. "If you read between the lines," he says quietly, the Antrim vowels softer than they used to be, "they're saying that I'm a very one-dimensional jockey. I don't know how to look at that. I'd have thought a one-dimensional jockey wouldn't ride as many winners as I do. Because every horse is different and I don't remember riding every horse the same way."
Nonetheless, the jury is still out on the question of whether it was McCoy's error at Newbury, or Denman's. McCoy leaves no doubt what he thinks. "Up until he made the mistake he didn't feel like a horse I wasn't getting on with. But if anything, there's less pressure on him, and me, than there was. The experts are all expecting Kauto Star to win now. All the pressure's on him."
Maybe, and yet the Gold Cup is not a two-horse race, any more than Cheltenham is a one-race meeting.
The horses owned by his retainer, JP McManus, will make up the majority of his Cheltenham mounts, though McCoy concedes that "JP doesn't have as many good ones as we would like. But he has plenty of chances at Cheltenham.
"It's true that he has no real flagbearer horse. When I started riding for JP, he had Baracouda, and it's hard to replace horses like that. Ruby's lucky. He has Kauto Star, Master Minded, Big Buck's, and he's entitled to ride them because he's a brilliant jockey, but..."
But... it's a sentence he scarcely needs to finish. The best chance of a McManus-owned, Jonjo O' Neill-trained, AP McCoy-ridden winner looks like Get Me Out Of Here in the festival's opening race, the Supreme Novices' Hurdle.
"Captain Cee Bee will probably be favourite for the Arkle," adds McCoy, of his Eddie Harty-trained mount in Tuesday's second race. "It's probably the hardest race of the festival to win, two miles flat to the boards. You need luck."
But luck is something McCoy has never relied upon for success. Practically everyone in and around National Hunt racing theorises about the differences between AP and Ruby in the saddle, but what are they from, as it were, the horse's mouth?
"I don't know that there's a lot. He's probably a lot quieter on a horse than I am. We're all different. Frankie (Dettori) sits a lot quieter than (Kieren) Fallon."
Jump racing, however, is lucky to have a jockey of McCoy's talents, and not just because of his achievements in the saddle. He cares deeply about his sport, and challenges the way in which it is run. He recently made an eloquent case for having fewer race meetings and more prize-money. And if it were left to him, he would abolish entrance fees at all but Cheltenham and the grandest meetings.
"If people feel they're getting a little bit of something for nothing, they'll show up," he says. "Once they're in, there are bars and restaurants, ways of getting them to spend money. But it's impossible to get money off people if they're not there."
His beloved football could do with the same economic acumen. McCoy is a devoted Arsenal fan, and when asked what he -- who has broken so many bones -- would say to Aaron Ramsey as the youngster recovers from such a badly broken leg?
"He's got to believe that he's going to heal quickly," he says. "And he's got to want to be better than Cesc Fabregas. Lester Piggott and Liam Brady were my heroes when I was a kid, and obviously I was too heavy to ride on the Flat, so I targeted Richard Dunwoody.
"He was champion jockey when I started, so I wanted to ride more winners than him. That kept me motivated even when I was out injured. Ramsey should do the same with Fabregas."
As a fan, too, of the Republic of Ireland, has he forgiven the former darling of Highbury for the infamous World Cup qualifier handball?
"Thierry? What a scandalous carry-on." A grin. "No, I'd have done it myself..." And with that, McCoy shakes my hand and goes to change into his silks for the last race of the afternoon, on the favourite Carribs Leap. On which he duly records the 3,222nd win of a truly extraordinary career. (© Independent News Service)