Never has an NBA finals featured the same two teams for three years running. While it has occurred once in America's three other main codes, each instance took place in condensed competitions more than 60 years ago, before those games opened their doors to athletes of every race and nationality.
In baseball, the Yankees and Giants set a trio of World Series dates between 1921-23 - but that was 25 years before Jackie Robinson broke the colour barrier.
In football, the Lions and Browns played off for the NFL championship in three straight years between 1952-54 - but that was when 12 teams contested a title that wasn't yet called the Super Bowl.
And in hockey, the Red Wings and Canadiens met to decide three consecutive Stanley Cups between 1954-56 - but that was when the NHL included only the Original Six franchises.
It has never happened in football's European Cup and, closer to home, has never happened in Super Rugby, unsurprisingly for a competition so young.
There has been a trilogy of championship showdowns across the Tasman, where in the early 1960s St George recorded a hat-trick over Western Suburbs in a competition that preceded the NRL, but that again featured a restricted field of 10 teams.
In short, we're about to witness something incredibly rare and perhaps unlikely to happen again in our lifetime. Let's just hope - like the third instalment of the Godfather trilogy - it doesn't suck.
Which is a wish that must be made, because last year the Cavaliers needed three superhuman performances from LeBron James to climb out of a 3-1 hole and steal the title, a series that was followed by the Warriors' acquisition of Kevin Durant.
And after adding a former MVP to a team already boasting a two-time winner of that award, Golden State have cruised through these playoffs, sweeping three series with an average winning margin of 16.3 points a game.
Cleveland have been almost as dominant, falling barely shy of three sweeps while managing an average winning margin of 15.0 points. But they have faced question marks about their defence all season and are about to face one of the best offences ever assembled.
Still, now is not the time to quibble. Now, with the possibility of seven more clashes between these two titans, is the time to salivate.
And if the series does reach expectations to sate our collective appetite for sport at the highest level, surely this time we won't be left wanting more.