I'm a huge fan of Messi, and I strongly believe he's the greatest player of all time.
I think if Messi was a goalkeeper he would be a speck of dust in comparison to players such as Peter Shilton, Petr Čech, Peter Schmeichel, Oliver Kahn or even the somewhat diminutive for a goalkeeper Fabien Barthez.
Ronaldo has the physique to be a goalkeeper, much taller than Messi and more athletic.
Looking at great central defenders of their era such as Bobby Moore, Tony Adams, Alan Hansen, the great Paolo Maldini and even players such as Virgil Van Dijk or Rio Ferdinand - how can anybody say Messi could be compared to them? They were masters of their trade in their positions. Who would choose Messi in a left back position when they have better options such as the great Roberto Carlos and even players such as Ashley Cole and Dennis Irwin to name a few.
In the centre midfield, there were too many masters of their trade to simply allow Messi to walk in to the team. Even in the great Barcelona teams of 2009+ when Guardiola was manager, Xavi and Iniesta occupied those roles.
Playing Messi on the left wing or on the right wing makes sense, playing him in the middle behind a striker or as a sole striker does not. Who would choose Messi over Ronaldo Luís Nazário de Lima (the Brazilian great El Fenomeno)?
As for Ronaldo, if he was called upon to do it I am sure with his mental focus he would be able to play in literally any position if the manager asked him in an emergency including goal and no matter how bad he might play in those roles he would be better than Messi. That speaks volumes because Messi is definitely not the greatest player of all time, there is no one player that has played in all 11 positions on the football pitch to cement that title.
In a like-for-like position Diego Maradona (also a left footed player) was a greater player than Messi. What Maradona did for Argentina in both the Mexico 1986 and Italia 1990 FIFA World Cup competitions as well as for Napoli after his transfer from Barcelona was nothing short of miraculous. Even the legendary Pelé stated "Maradona was a much better player than Messi":
https://en.as.com/en/2018/12/06/football/1544122661_793685.htmlSaying any one player is the greatest in the position they play in might be a better way to debate it
However, for this poll I chose Ronaldo. I'd rather have Ronaldo on my team for a few reasons, the first reason would be his motivation/hunger for success. Ronaldo is always a player that is motivated and a better leader than Lionel Messi, and he puts in more than the extra needed almost at all times, he's never satisfied with his achievements and he's always eager for more, I'm not saying that Messi doesn't putting enough efforts, but then I'm just saying Ronaldo puts in more efforts and zeal, that's why I would rather have him on my team.
I have seen very few players that have the mental ability to push themselves further and never be happy with what they achieve so much so they are always hungry for more success. For me, Ronaldo is the player I would want in my team over Messi. It cannot be overstated how great a player Messi is but I think he will not be winning any more Ballon d'Or where as even with his age at 35 Ronaldo seems to be on fire at Juventus.
Outside of the Barcelona team, Messi has not really won anything of substance including almost nothing important with the Argentina national team though he has won 6 Ballon d'Or with Ronaldo on 5 Ballon d'Or awards. Ronaldo has won the English, Spanish and Italian league titles - unbelievable. He also has won the European Champions League with an English (Manchester United 1 time) and a Spanish team (Real Madrid 4 times), now trying to win it with an Italian team (Juventus). He has also became a national team European champion when the Portugal national team won the UEFA European Cup.
I have never ever seen a player do things with a football in a way that the great Diego Maradona did but he is not the greatest footballer because it is impossible to compute as nobody has played in every position over a long length of time to evaluate. In my opinion Maradona was one of the greatest in the position he played in on the pitch.