Cristiano Ronaldo and Lionel Messi are two of the greatest players of all time.
But who is better?
Many of the world's greatest managers in the world have answered the debate in the past.
Alex Ferguson, Diego Simeone and Jurgen Klopp are just three high-profile coaches that have given their opinion.
We've listed 10 legendary managers that have answered the debate and who they believed was better below.
Alex Ferguson - Cristiano Ronaldo
This isn't that surprising, given Ferguson brought Ronaldo to Manchester United and managed him for six years.
He outlined the differences between the two back in 2016.
“Now don’t get me wrong, Messi is a fantastic player, it’s like he’s wearing slippers when he controls the ball," he said in 2016, per Sports Illustrated.
"But here, for me, is the difference. Messi is a Barcelona player. But Ronaldo could play for Stockport County and score a hat trick. He has everything. He can shoot with both feet, head the ball, he’s as brave as a lion..."
Fabio Capello - Lionel Messi
"It's one thing to be an outsider, and another thing, to be a genius," he told Marca, per calciomercato.
"The difference is enormous, since a genius does what nobody imagines. Ronaldo is an extraordinary footballer, but Messi is a genius."
Diego Simeone - Lionel Messi
A leaked WhatsApp clip in 2018 appeared to show Simeone claiming Ronaldo was better than Messi.
He clarified those comments shortly after and said that Messi was better.
"If I had to choose between Messi and Ronaldo then most likely I would choose Messi," Simeone told reporters, per Goal.
"Yes I said [Ronaldo] on the video, but the conversation was between me and [Atleti assistant] German Burgos, talking about football as everyone talks about it.
"When I talked about Messi and Ronaldo it wasn't from the perspective of who is the best in the world.
"I just meant that if you have the chance to sign one of them for a normal club, with normal players, Ronaldo would probably fit in better.
"But with Messi, surrounded by great players, Messi is better than Ronaldo."
Jurgen Klopp - Lionel Messi
Klopp made it clear he thought Messi was better when speaking at a Q&A in 2018.
“I have only one selfie on my smartphone. That’s with Messi. Cristiano Ronaldo was in the room as well…”
Zinedine Zidane - Cristiano Ronaldo
Zidane managed Ronaldo for many years so it's not much surprise he went with the Portuguese.
“Cristiano is the best. Messi is his rival and it's the rivalry everyone wants to see,” the Frenchman said.
“But Ronaldo is phenomenal. There are no words to describe him. He is much better than me even though I had a great career. He's the greatest of all time.”
Jose Mourinho - neither
In 2013, Mourinho said Ronaldo was the best. Three years later, he named Messi and not Ronaldo in his three greatest players of all time.
But, speaking to BeIN Sports last year, Mourinho refused to pick a favourite.
“I think it’s unfair to both of them when somebody [says] this one is better than the other one. I think they are just different,” he commented.
“When you go to Messi and Ronaldo, I think it’s just unfair to compare the players. The only thing I can say is that when I had Ronaldo on my side, I was a very happy man.
“And when I had to play against Messi - and also against Ronaldo because I played against Ronaldo a few times - I had to think a lot to try and help my team have chances to succeed."
Pep Guardiola - Lionel Messi
"Messi is the best, he is definitely the best," he said, per ESPN. "He knows how to play, score and make the other players play. He is always there.
"With all the respect to all the players, first to Cristiano Ronaldo -- congratulations to him for the award -- I think Messi is on another level."
Joachim Low - Lionel Messi
The World Cup winning manager was asked the question by Bild in 2018 and he went with Messi.
"I would stick with Messi," Low told Bild, per Goal.
"Cristiano Ronaldo is sensational, a very good professional, an incredible goalscoring machine for many years, but Messi is the most complete player I have seen.
"He is a great team player. He's provided 30 to 40 assists for the last 10 years as well as scoring around 50 goals.
"He's capable of leaving eight or nine players in his path and his goals always stay in your memory."
Arsene Wenger - neither
Wenger was asked about who he thought was better last September. Wenger doesn't like to compare the two, but did say managers would be more tempted by Messi.
“I would say that they are so good that it’s difficult to choose – in 10 footballers of the year, it’s five and five, so that shows they are really on the same level.
“Artistically, Messi is as well a guy who can give the final ball, so he’s maybe more a creative player than Ronaldo.
“Ronaldo is more a finisher, better in the air, more athletic, and Messi is the more artistic.
“So basically you are always tempted a little bit more by a player like Messi.”
Vicente Del Bosque - Lionel Messi
Real Madrid legend and World Cup winning manager Del Bosque went with Messi.
"He [Messi] almost always plays well," he told Mundo Deportivo, per Goal. "There are players who never do it wrong. He has an impressive regularity. He is a great player.
"I'm staying with Messi. I see a more natural soccer player, from his time in the neighbourhood, playing with friends on the street. Even so, Cristiano has extraordinary courage, with physical and technical conditions as a great scorer, but I'm staying with Messi."
Lionel Messi - 6
Cristiano Ronaldo - 2
Neither - 2
Out of the 10 great managers listed above, the majority went with Messi over Ronaldo.
But we think Wenger and Mourinho put it best. Both are both incredible footballers and will go down as two of the best ever.
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