The Barcelona ace and the Real Madrid superstar have been locked in a fierce battle for supremacy for the past decade.
Both players have won a significant amount of trophies with their respective clubs as well as plenty of individual honours.
It is largely an impossible task to end this debate. Whoever you prefer, fanatics for the other will try their loudest to shout you down.
On Saturday, the official Champions League account wished Messi a happy 30th birthday, with the caption "The Greatest?"
And the birthday tweet has caused rival fans get heated once more over who is better.
Happy 30th birthday Lionel Messi!— Champions League (@ChampionsLeague) June 24, 2017
The greatest? pic.twitter.com/25hZnXscEf
The greatest pic.twitter.com/dLGt4mBSOU— Yashay (@YashayM_) June 24, 2017
Can't understand how people genuinely think Ronaldo is a better player than Messi— Nathan (@simmobbc) June 24, 2017
you spelled ronaldo wrong— 🐝+*🦋 (@macdaddytee) June 24, 2017
Of course the greatest !!! And to those who don't think so, in Maradona's words, well keep sucking it— HAM (@_HAM666) June 24, 2017
THE GREATEST PLAYER OF ALL TIME pic.twitter.com/J8ywJadFGl— mx (@BUSQXETS1) June 24, 2017
The GREATEST! 🐐 pic.twitter.com/UtMW343ub3— #AporLaDecimoTercera (@Clement_Madrid_) June 24, 2017
Easily the greatest of all time— TitanOfRacing (@titanofracing) June 24, 2017
Best player...... after cristiano.....— Ali Mughal (@AliMughal_007) June 24, 2017
You don't have to question mark that...He's the greatest— hAYwHY (@iamayodaramola) June 24, 2017
The most impactful player in the history of football is Cristiano Ronaldo. Argue with your anthem https://t.co/Yeb5nk7m7h— Abu Zidan (@dinstots) June 24, 2017
The greatest there is, the greatest there ever was and the greatest there ever will be. Nobody comes close to him and ever will— #L30Messi (@CampNouBall_Boy) June 24, 2017
The Maestro! 🙌 pic.twitter.com/TDbrOXOSXn— Victor O. Àbàtì (@Victor_O_Abati) June 24, 2017
I am. A Real Madrid fan , but Cmon Just Look at Leo He is Undoubtedly the best player of all time— Anime Freak (@animefreak22134) June 24, 2017