When playing for FC Barcelona, Messi has Xavi and Iniesta providing him with service—easily two of the best central midfielders in the world. Those two maestros excel at providing Messi with service that puts him in threatening positions, often finding him around the periphery of the penalty area, or through balls that find his darting runs into the box.
Clearly they do a great job and Messi thrives off their brilliance. However, any time that he plays without them you see a completely different player. Yes, defenders still find it nearly impossible to strip him off the ball without having to foul him, but he is nowhere close to the efficiency he shows when he plays at Camp Nou alongside his super friends.
His all-around performances with the Argentina national squad have been dreadful and are painful to watch. He is highly criticized for this.
While he was better during July's Copa America, he often does what Nicolas Anelka once did for the French national team, dropping deep to get more touches on the ball. During difficult games, Messi often looks to spark life into his side by going it alone. He has the talent to do it, but well-disciplined defenses can snuff out his runs effectively.
After all, he can't go all Getafe on every team he faces.
Cristiano, on the other hand, continues to score regardless of who his teammates are. Since vaulting into the spotlight during Euro 2004, he has managed to succeed with more than one soccer club.
He is brilliant at creating his own shot opportunities and can score in any number of ways.
Though many critics may say he is a ball hogger for this, keep in mind that Cristiano has still managed to score twenty plus goals for the past five seasons, including two seasons in which he was been awarded the European Golden Boot.