The most common fixture in European football: Bayern take on Real for the 25th time Ronaldo is in fine form heading into the last-four clash. LONDON: Perhaps the most remarkable feature of Cristiano Ronaldo’s career is how he has reinvented himself. It is not just that he has reduced his effective playing area each season, transitioning from fast dribbling winger to souped-up target-man, it is that in doing so he has made himself a more effective player — and that is what must trouble Bayern Munich, who have in the past exposed his flaws, before today’s Champions League semifinal. Ronaldo was always a flawed genius. He had immense dedication and turned himself into the physical embodiment of the ideal player, powerful and quick. He could beat opponents for skill but he could also beat them for strength. And yet there was always a sense that the game was about him and not about the team. If he was chasing the golden boot, he would shoot from ludicrous positions rather than passing to better-placed teammates. After Manchester United had beaten Chelsea in the Champions League final in 2008, despite Ronaldo missing a penalty in the shootout, he sat alone in tears as the rest of the side celebrated in front of the United fans. Similarly, his celebrations after scoring the penalty that gave Real Madrid a 4-1 lead in the 120th minute of the 2014 final seemed excessive for a goal that meant almost nothing. But worse was his neglect of his defensive duties. That was why Sir Alex Ferguson began using him as a central striker in the 2007-08 season, realizing that Wayne Rooney would be far more diligent in tracking the opposing full-back. The Champions League semifinal in 2012 was a perfect illustration of the problem. Ronaldo set up Mesut Ozil’s goal as Madrid lost 2-1 in Munich and then scored twice early on at the Bernabeu in the second leg. But it was his failure to check the forward surges of Philipp Lahm from full-back that ended up costing Madrid the game. The same self-obsession that had made him such a great physical and technical player was also what made him a tactical problem. It is why, until very recently, he had won relatively little. This is his ninth season in Spain, playing for one of the two richest clubs in the world, yet he has won only two Spanish league titles. His conversion into a central striker, while it may make Madrid a little more predictable, has also made them a better-balanced side. There is no danger now of the opposing full-back having the run of the flank. Few full-backs had the chutzpah to call Ronaldo’s bluff and drive past him, risking leaving him untended. No center-back will and, even if they do, a player moving into central midfield where there are more bodies is less likely to pose a threat than a full-back advancing into the space that more naturally occurs on the flank. And Ronaldo’s finishing, particularly in big games, has been remarkable. He has scored six goals in four games in the knockout stage so far this season — including that overhead kick against Juventus — to go with 10 in the knockout stage last season and five the season before. He is now a player of a type the world has perhaps never seen before: A combination of poacher and target-man all mediated through the technical ability that initially made him stand out as a winger. His involvement in games is often minimal, until he scores the goal that turns the tie. It is not something every side could get away with, but Madrid have enough in midfield that they can carry a player who gives them such cutting edge — provided he plays centrally. And Bayern will doubtless be all too aware of that. KEY CLASH ARJEN ROBBEN vs MARCELO Just because Cristiano Ronaldo no longer plays on the flank doesn’t mean that a winger vs. full-back battle will not still be key. Arjen Robben may be 34, but he remains the most dangerous creative player Bayern have. Defenders may know he is going to cut inside onto his left foot and shoot but they still seem unable to stop him. That means that Marcelo, particularly in the first leg in Munich, is likely to be tested — and for all his many, many qualities as an attacking full-back there have always been questions about his defensive caliber. Similarly, if Madrid can gain a foothold in midfield, Marcelo’s surges past Robben — and the Brazilian will surely have the edge for pace — could be a potent attacking outlet for Madrid.