Their rise to the very top of the game has been a given ever since their enrolment into the La Masia academy at Barcelona.
Both have been at the very epicentre of the recent successes for Spain and the Catalans and are twin talents that have provided manna from heaven for the football purist.
The cogs that oil both machines have rarely let their employers down since bursting onto the scene, and their astonishing consistency places them at the very pinnacle of the world game.
Lauded worldwide for their individual and collective talents, how do you go about making a case for who is actually the best?
Purely based on trophies won it is Hernandez, the embodiment of Barcelona's tiki-taka philosophy, who is out on his own.
Taking into account the Spanish Supercup success at the start of this season, Xavi now has 25 trophies to his name, making him the most successful player in Spanish football history, per FCBarcelona.com.
Vicente Del Bosque even alluded to Xavi being "very important, more so than the coach" per Marca.
With 813 passes in the final third of the pitch, per WhoScored.com, Xavi is the player with the most completed in the entirety of the top five European leagues during 2013/14 season. His contribution and value is obvious.
WhoScored also detail Xavi's astonishing passing averages across the season. 93.3 passes per match with a completion rate of 93.7 percent.
Is it any wonder that fellow players, fans and media alike deign to his genius. Barney Ronay of The Guardian is just one of many:
No footballer has ever played such a decisive role in victory at three major international tournaments, or defined so clearly the dominant club team of the age.
Xavi has won 25 major trophies, made more than 180 assists for more than 50 team-mates at Barcelona, and has over the last six years passed the ball more than anybody else, run more than anybody else, and basically played more football than any other human being anywhere.
As we have witnessed many times throughout his record-breaking career, Xavi is the conductor of the Blaugrana orchestra, the conduit through which everything flows.
His is a perpetual motion that is elegance personified, a swiss-watch accuracy of pass never bettered.
The real pleasure one derives from his game is that it is so uncomplicated. Football at its most pure. "You give me the ball, I pass the ball" is Xavi's mantra. Nothing fancy yet a quality in his work that elevates him above his contemporaries.
Tim Rich of the Daily Telegraph notes Sir Geoff Hurst's words on his former manager at West Ham, Ron Greenwood: "Simplicity is genius."
It's a quote that perfectly defines what Xavi Hernandez is all about but at 34 years of age, there isn't much time left to enjoy such genius.
It would be fair to assume that the entire dynamic of the Barca, and perhaps Spain, midfield will change once this most unassuming of midfielders takes his final curtain call.
With such a glorious professional resume, how close does Iniesta come to matching up to his team mate?
To start, if we compare his passing stats with those of Xavi, Iniesta's average of 67.5 per game is inferior, but his completion rate of 90.6 percent is up there in the same ballpark. Three goals and seven assists this season is more decisive than Xavi's three goals and two assists, via WhoScored.
Xavi's game is based around the pass-and-move philosophy that has become Barcelona and Spain's trademark, whilst Iniesta has an inventiveness and a guile to his play that is beyond compare.
Like the matador ruffling his muleta to seduce the bull, only to step aside at the last possible moment, Iniesta's control is total, his dazzling footwork poetic, and his gentle caress of the football like a young father cradling his newborn. Ole!
Some of the things that he does within a game scenario are scarcely believable, magical even. He was handed the moniker of "El Illusionista" (The Illusionist) for obvious reasons. There really aren't enough superlatives to justifiably describe his impact on the game as a whole.
It's no surprise then that he is so highly revered within the game itself, and if the words of his contemporaries are anything to go by, popular opinion decrees that he is up there with the very best exponents in world football.
Of Juan Roman Riquelme: "I watch Iniesta and realise that even at my age I could be learning new things."
Of David Silva: "The press often ask me about whether Messi or Ronaldo is the best, but for me something is very clear. Andres Iniesta is the number one."
And of Sergio Ramos:
He is the enlightened one. Someone touched by a magic wand. He commands so much respect on the pitch. As a football lover I am proud to have played with him. He makes the difference and does things that no one else can do.
There are many others, too, that are all too willing to lavish such blanket praise on the little man from Fuentealbilla.
On a personal level, Iniesta has scored some of the most important and momentous goals in the history of both Barcelona and Spain.
No one will ever forget this beauty at the very end of the 2009 Champions League semifinal against Chelsea:
Without such an intervention, Barca simply would not have been heading to Rome and completing the only treble in La Liga history.
Just a year after and Spain's first World Cup was won courtesy of Don Andres:
At 30 years of age, Iniesta certainly has a few more years left in the tank, and he will no doubt write more chapters in the history of the Blaugrana and La Roja.
Although he still has some way to go to catch up with Xavi's appearance record for both sides, few would bet against him achieving it. But will it make him more important or more relevant than his team-mate?
The question as to who is better is one that cannot readily be answered. It's the Lamborghini or Ferrari scenario again.
Slight differences and nuances that make them individual, but both are the very best at what they do.
Loved for the rich tapestry they have woven throughout their careers, the biggest compliment that one can pay Xavi and Iniesta is that Spanish football will never be the same once Old Father Time pays a visit.
Enjoy them while you can.