Gretzky-Lemieux. Bird-Magic. Ali-Frazier. Borg-McEnroe. Nicklaus-Palmer.
And soon, another entrant will be welcomed into the pantheon of sports' greatest rivalries: Sidney Crosby versus Alexander Ovechkin.
The Penguins captain and Capitals' goal-scoring machine will both be in action Saturday on Hockey Night in Canada.
Crosby's Pens visit the Ottawa Senators for a matinee game (CBC, CBCSports.ca, 2 p.m. ET), while Ovechkin's Caps visit the Toronto Maple Leafs at night (CBC, CBCSports.ca, 6:30 p.m. ET).
Since entering the NHL, Sid the Kid and Alex the Great have captured the imaginations of hockey fans around the world, while playing a key role in helping the league recover in the post 2004-05 lockout era.
With equal parts style and grace, scoring skill and playmaking ability, Crosby and Ovechkin have won both the Art Ross and Hart Trophies in successive years (Crosby in 2007, Ovechkin in 2008), while at the same time firmly establishing themselves as the cornerstones of the NHL.
There's more to come, too. Crosby is only 21, Ovechkin 23, and they're likely not even in the prime of their respective careers.
Sid the Kid and Alex the Great
With these two leading a generation of exciting young superstars, the NHL has little to be worried about in the immediate future in terms of the on-ice product.
And it'll be only a matter of time before the Crosby-Ovechkin showdown eclipses hockey's most hallowed and greatest rivalry: Wayne Gretzky versus Mario Lemieux.
That might sound like blasphemy. Gretzky and Lemieux are considered the two greatest players ever to play the game by most critics, but the rivalry between No. 99 and No. 66 was missing something the Crosby-Ovechkin contest has in abundance: a potential for longevity.
Gretzky was in his seventh year as a pro (including one year spent in the now-defunct World Hockey Association) when Lemieux made his debut as an NHL rookie in 1984. While their NHL careers certainly overlapped, Gretzky and Lemieux weren't in their primes at the same time, save for a two-year period from 1987-89 when they went toe-to-toe for the Art Ross Trophy.
Crosby and Ovechkin, on the other hand, entered the NHL together as rookies in 2005, coming along at a crucial time in the league's history, when hockey-starved fans were craving action and a new crop of stars.
It set the stage for the incredible rivalry between the two young men.
"Both players entered the league at the same time, in the first year after the lockout, which is an important consideration," said Hockey Night in Canada Radio host Jeff Marek.
"And not that the rivalry is a media fabrication, but the league needed a great new story to tell and this was the best one going: good-looking young phenom from the Maritimes who had Wayne Gretzky's magic wand waved over his head, against the flashy star from Russia who heralded in a new breed of Russian athlete: slick, physical, with an ability to bring fans out of their seats."
The right stars and the right time
Of course, hockey fans were able to whet their appetite on the rivalry before either played an NHL game, a fact that further heightened expectations.
"It helped that hockey fans knew the backstory of both these players before they even entered the NHL. While the NHL locked out it's players, hockey fans looked elsewhere and found Crosby leading Rimouski to the Memorial Cup finals and Crosby and Ovechkin going head-to-head in the gold medal game at the world junior hockey championship in 2005," Marek said.
"The NHL didn't start this story, the hockey world did. The NHL was merely the beneficiary."
Another thing Crosby-Ovechkin has over Gretzky-Lemieux is the era of the rivalry.
"A lot of it has to do with the information age that we live in and that the Crosby-Ovechkin rivalry is being promoted, discussed, debated not just on TV, but also sports radio, newspapers, internet," Marek said.
"It's a great discussion point for the NHL and one the league is only too happy to continue to perpetuate. These two play in the same conference so it naturally follows that the media gets plenty of chances to play the rivalry up. Nobody talks about that Crosby-Zetterberg or Ovechkin-Iginla rivalry because, let's face it, how often do they face one another?"
Indeed, Gretzky and Lemieux only played in the same conference very late in their careers, when No. 99 was with the Rangers from 1996-99, and even then, Lemieux played only one of those seasons because of health problems.
There are other forces at work here, not the least of which is the widely held belief that Lemieux was a reluctant superstar, and lacked the same drive and ambition as Gretzky.
"They never pushed each other the way Crosby and Ovechkin do," said Marek. "We never got the feeling that Lemieux wanted to be the best and surpass the greatness that was Gretzky. If there ever was a reluctant superstar in the NHL it was Lemieux.
"He had perhaps the greatest singular skill set the game has ever seen but Mario never wanted to work hard enough to see how far that could take him, whereas Gretzky worked harder than anyone on his teams and left nobody wondering how good he could be. We saw it all."
And, of course, there is the potential for the Crosby-Ovechkin rivalry to leave a lasting impression in the international game, as they are expected to be key members of the Canadian and Russian national teams at the 2010 Olympic Games in Vancouver.
So, what we should expect from Crosby and Ovechkin this season?
"We should see Ovechkin blow away the field for the Maurice Richard Trophy and both should battle game in, game out for the Art Ross and Hart trophies," opined Marek.
"It'll be interesting to see whose team fares better in both the standings and playoffs. … With any luck, they'll meet each other in the post-season."