What is it that earns the title of best for the best players in world football? Technical quality aside, what traits make them stand out?
Technique alone isn't enough. Otherwise, Adel Taarabt might have won a Ballon d'Or, and Georgiou Kinkladze would have won five. Instead, more is required, and not just more attributes to a player's game but always wanting more: Success is never enough, personal bests can always be beaten and a record is just a matter of time.
The two greats of the modern game, Lionel Messi and Cristiano Ronaldo, have every major attribute between them: on-the-ball technique, finesse in the finish, rock-solid personal belief, a winning mentality, great physical capacities and the knowledge of how best to use it—and above all else, unrivalled, relentless consistency.
That latter is what made Messi and Ronaldo the best in the world by 2008, the first time either of them won the Ballon d'Or (Ronaldo first, Messi second on that occasion), and that is exactly what has kept them there almost a decade later.
Nobody else has come close; only in 2010 since that first victory for Ronaldo have the duo not occupied spots No. 1 and No. 2 in either order.
Along the way they have not just won trophies but also broken records with an ever-increasing frequency, proof of their greatness and the enduring legacies they will leave behind.
And they are not finished yet.
La Liga and Spanish Football
Domestically, Messi and Ronaldo's chances of success—both team and individual—are markedly improved by the fact their sides are the top two in the country. Last season, they completed a clean sweep: Real Madrid took La Liga and Barcelona the Copa del Rey and Spanish Super Cup. Real have started this term with the Spanish Super Cup, and the title fight will probably be between the duo once more.
As for records, we may as well start with the silverware. Messi has the chance to become the player who has won the most trophies in Spanish football, a title he shares with team-mate Andres Iniesta, 30 apiece.
Naturally, it will require either Iniesta to depart or, as has been frequent over the past 18 months, injury to force the Barca No. 8 to miss out in a cup final or similar if Messi is to take sole leadership of that stat.
Then there are the goals. So many, many goals.
In matches between the two sides, El Clasico, Messi is out in front; he has 24 competitive strikes and can naturally increase that total this term.
But Ronaldo has a record in sight: the most goals for a Real Madrid player in El Clasico. He trails Alfredo Di Stefano by a single strike, 18 to 17.
In more general scoring terms, the Real Madrid man can become only the second player to hit 300 goals in La Liga—after Messi—but the first to do so in under than 300 games (it took Messi 334 games, per Antonio Rusinol of ESPN Stats & Info).
Come the end of the season, they will both be fighting for top-scorer honours, not just in Spain but beyond. Messi and Ronaldo share a record of four European Golden Shoes; if one manages it for 2017/18, he will hold that record outright.
The only player other than Messi or Ronaldo to win the Golden Shoe since 2009/10 is Luis Suarez, twice, and it should be noted that one of those years saw Suarez share it with Ronaldo, while Messi's four were won outright.
Finally, Ronaldo could increase his hat-tricks record, which stands at 32 in La Liga.
In the Champions League, Ronaldo has been the recent big success; his team won back-to-back titles in 2015/16 and 2016/17, the first team to retain the trophy in the modern era.
He's also flying on an individual level. He's the all-time top scorer with 105 goals, the only player to net over 100 goals in the Champions League and the only player to score in three finals since the competition's rebranding in 1992.
What else is left to achieve? Plenty, as it happens, and not just for Messi trying to catch Ronaldo—he's 11 behind his generational rival in competition goals.
Both Messi and Ronaldo have seven Champions League hat-tricks, a record, and the first to notch the next will take the title...for a short time only, no doubt, as they vie for supremacy. But the quickest treble is still up for grabs.
Bafetimbi Gomis is the unlikely player who holds that record, scoring three times in eight minutes for Olympique Lyonnais in 2011. While Messi and Ronaldo are capable of great goalscoring feats at a moment's notice, perhaps the most likely opportunity in the group stage will come for the Real Madrid man as his team faces APOEL of Cyprus.
Messi is aiming to become the second player to reach 100 Champions League goals and also the first Barcelona player to hit 100 in UEFA competitions.
Additionally, should Barcelona go on to win the trophy, he will overhaul Xavi Hernandez as the Barca player with the most Champions Leagues won for the club—level with Iniesta. All three have four. One more Champions League for Ronaldo will see him move joint-second in the all-time list as Paolo Maldini, Alessandro Costacurta and Di Stefano also have won five trophies.
Only Paco Gento has more with six.
Then there are one or two head-to-head battles to take records outright. They share the most penalties scored in Champions League history, 11 each (from 14 taken each—also a record, incidentally).
Both Messi and Ronaldo have the chance to beat Radamel Falcao's record of 18 goals in a single UEFA competition season—the Colombian netted one in qualifying and 17 in the competition proper during the 2010/11 UEFA Europa League campaign. Ronaldo finished one short of that tally in 2013/14, a Champions League record. Messi's best is 14.
Finally, beyond the Champions League, Ronaldo requires just one goal at the FIFA Club World Cup to become that competition's all-time top scorer. He shares the record with Suarez and Messi (along with Cesar Delgado), each with five, but only Real Madrid will be there this year.
Both are rivals domestically and in European football, but they also both have records to chase on the international scene—particularly with a FIFA World Cup looming large at the end of the campaign.
It's worth noting neither Portugal nor Argentina are looking assured of a spot in Russia. The European nation sits second in its group with two games to play and may need a play-off to reach the finals, while the South Americans sit fifth in the CONMEBOL group. The top four go through automatically; fifth takes a play-off berth.
Ronaldo is already the record caps holder and record goalscorer for his nation, so he will seek to extend and improve both, but he has other big targets to reach.
The Portugal captain has just three goals at the World Cup, so he needs a huge haul to get anywhere near the highest-ever scorers, Miroslav Klose (16) and Brazil's Ronaldo (15).
Messi, meanwhile, is top scorer for Argentina overall but needs five more to equal Gabriel Batistuta's haul of 10 at World Cup finals for his nation and six to surpass Batistuta. It's achievable but would likely need him to be top scorer for the tournament—nobody has surpassed six goals in a single World Cup since 2002.
In terms of caps, Messi will fall a little short this year in his progression towards being Argentina's most-capped player; he's 24 shy of Javier Zanetti's 143. Even if the South American nation goes all the way to the final and Messi plays in every warm-up friendly, he's only likely to get a maximum of 16 games across the next 10 months.
It will come, no doubt; in the meantime, there are plenty of more notable records ready to fall between the two.