To paraphrase George Orwell, all NBA Finals games are equal, but some are more equal than others. After splitting the first four in what’s been a back-and-forth series, the Miami Heat and San Antonio Spurs are set for an epic Game 5 on Sunday. It’s essentially a must-win for San Antonio. A loss would mean winning Games 6 and 7 in Miami against a team that hasn’t lost consecutive games in months. The stakes couldn’t be higher, particularly for the two all-time greats set to take the stage.

Even in a series with future Hall of Famers all over the court, LeBron James and Tim Duncan stand out. The seemingly ageless Duncan, a first-team All-NBA center at the age of 37, is averaging 15 points and 11 rebounds in his fifth NBA Finals. LeBron, a 28-year-old at the apex of his powers, is averaging 21 points, 12 rebounds and six assists a game ... and people want him to do more! How many NBA Finals have ever featured two of the ten greatest players of all-time?

All transcendent basketball players share a few things in common. They have the size and athleticism to dominate at multiple positions and they don’t have any holes in their game. Duncan helped usher in a new era as multi-dimensional 7'0 power forward, although age has caused him to slide down to center. LeBron, a 6’9, 270 point guard/center hybrid, is something we've never really seen before. Both can score, pass, rebound and defend at an elite level. In this series, their only weakness has been an inconsistent jumper.

Unselfishness is what separates them from many of the NBA's pantheon players. Over the course of their careers, both have consistently been fantastic teammates. They don't force the action and let the game come to them. It’s impossible to imagine either getting into the type of locker room struggle that eventually broke up Shaq and Kobe. There isn’t a team in the history of the league they couldn’t seamlessly fit into. They're all-time great players who play the game “the right way”.

From a historical perspective, the great tragedy is they never faced off at the height of their powers. When they met in the 2007 Finals, LeBron was only 22, still years away from his prime. A prime Duncan, meanwhile, would change everything about the 2013 Finals. Rather than serving as a ball-mover and secondary option, he would have dominated Chris Bosh in the low-post. On defense, he would have shut down the paint, forcing LeBron and Dwyane Wade to play as jump-shooters.

As great as LeBron is, there’s very little he could have actually done against a 28-year-old Duncan. Duncan has four titles on his resume and he’s this close to having many, many more. He’s literally two plays -- Derek Fisher’s 0.4 shot in 2004 and Dirk Nowitzki’s and-1 in 2006 -- from winning five straight titles. He faced a Lakers team with two all-time greats in their prime and defeated them twice. Were it not for Shaq, Duncan could have had a Bill Russell-like run through the 2000’s.

For Duncan, a title in 2013 would be the capstone to one of the greatest careers in basketball history. The awards speak for themselves: 14 All-NBA teams, 13 All-Defensive teams, two MVP’s, three NBA Finals MVP’s. He would be the first player since Kareem Abdul-Jabbar to win a championship as a first-team All-NBA player in his early 20’s and his late 30’s. David Robinson and Tony Parker are great, but they aren't Oscar Robertson and Magic Johnson.

For LeBron, a title would be be the capstone for one of the greatest three-year runs of all-time. Russell won championships as a player/coach, but no one has won as a player/GM before. Practically every important player in Miami -- Wade, Bosh, Udonis Haslem, Mike Miller, Shane Battier, Ray Allen -- took less money in free agency in order to play with LeBron. If LeBron becomes a GM, he will probably be more Larry Bird than Michael Jordan.

No matter what happens over the next week, winning in 2014 will be a tall order for the Heat. No team has made four consecutive Finals since Bird’s Celtics. Climbing the mountain every year takes a toll, physically and mentally. LeBron and Bosh are their only core players under 30. Everyone else has shown signs of wearing down. And with rumors flying about Chris Paul and Dwight Howard, they may have to face the ultimate challenge in 2014: a superteam created in their own image.

In that respect, a loss to the Spurs could sink any realistic chance LeBron has of “catching” Kobe, much less Jordan. Regardless of whether it's fair or not, the Big Three will be judged by the standard they gave themselves three years ago. More than any team since the Shaq/Kobe Lakers, if the Heat ain’t first, they're last.

The pressure surrounding the team, both on and off the court, is palpable. Everything that happens to Miami is the biggest deal in the world, one way or the other. It’s crazy.

That may be the biggest difference in the way Duncan and LeBron approach the game. No one who unironically calls himself “King James” and has “The Chosen One” tatted across his back can say he doesn’t have an ego. Duncan, in contrast, might as well be a Buddhist monk when it comes to operating without one. He loves basketball, but it’s his job, not his identity. You don’t get the sense he spends too much time worrying about legacy or Q rating.

LeBron, unlike Duncan, has transcended the sport he plays in. He’s as famous as any one person can possible be. Until you see it in person, it’s hard to grasp the level to which his life has become a reality show. During timeouts, one of the ABC cameras follows him around the court, to the complete exclusion of anything else going on. It’s a good metaphor for how people view the series. Duncan will probably be remembered mostly for being “boring”, but the older I get, the more I see why that isn’t such a bad thing.