He is almost unstoppable as witnessed by the lamentations of many a manager throughout the world as they describe what I call the Ronaldo paradox. Essentially Ronaldo knows that he is going to beat his man, either with the ball or by winning a foul, so what he does is he runs straight at them and if they show him away from goal he beats them down the flank and if the other occurs he reciprocates and cuts in to shoot on goal. And if they commit Ronaldo simply has to knock the ball past them and go down with the inevitable contact. Messi uses his quick feet and low centre of gravity to squeeze his way through defenders but when teams assign more players to him inevitably this system becomes a lot harder. If the player commits, which more often than not they do, then Ronaldo will be able to use his knuckleball technique to bamboozle the keeper. Only a few players notably Bale and its creator Juninho Pernambucano have come to grips with this system and it is evident to many that Ronaldo has mastered it. I hope this is not too damning on Messi because he can strike a dead ball, but I think everyone has to give this accolade to Ronaldo and not Messi.
Ronaldo and Messi have time and time again proved themselves to be outstanding players possessing better understanding and better technique than any other player. However, Ronaldo has done this at every club he has been at from Sporting Lisbon and Manchester United to Real Madrid. Ronaldo has braved the likes of Stoke and the notorious physicality of the Premier League and come though them unscathed, whereas it is hard to imagine Messi adapting to the rather more size-orientated aspect of the Premier League especially without his buddies Xavi and Adres Iniesta. Which brings me onto my next point: conveniently Messi has always, from an early age, had the benefit of playing with two of the best passers, and thus assisters, in the world. Taking nothing away from the likes of Mesut Ozil and Xabi Alonso, Ronaldo simply doesnt have the same service from Madrid. It sounds ridiculous to say he has to make do with what hes got when referring to Real Madrid but in reality Ronaldo is the framework, trigger and bullet of Madrid whereas Xavi, Iniesta and Messi are the respective elements for Barcelona.
Messi is a superb player but recently tendencies to become completely shut out from a match have crept into his game whether from industrious defending or simply an off-night which cannot happen to the best player in the world. It is very rare that Ronaldo has a bad game, and also rare if he doesnt score, but even if he doesnt get on the scoresheet he will have played his part admirably and will have influenced the game in some form or another. Messi is all about goals (as should any striker be) and has broken almost every record there is to break and this is what distinguishes him from the rest of the world, but Ronaldo has chipped in with more than his fair share of goals, scoring 200 in 197 games for Madrid an average of 1.02 goals a game. whereas Messi averages a meagre (yes, of course Im joking) 0.82 goals a game for Barcelona.