Kylian Mbappe's moment has finally arrived - but is there a risk he makes Real Madrid worse?!

Mbappe really should have completed a few seasons in Madrid white by this point. He has rejected Real twice - both times bringing about the special type of indignation expressed only by fans of the club. He has been warned, on numerous occasions, that Los Blancos will never allow him to wear the shirt.

Yeah... about that. He's here anyway, and on pretty reasonable terms. Yes, he will be handed a gaudy signing-on bonus of €150 million (£128m/$163m), spread out over the course of his contract. Yes, there will undoubtedly be all sorts of fees and terms not made public. But Madrid didn't have to pay a cent to PSG to make this all happen. The only real pain point is that it took this long.

Madrid won the Champions League last year without him, anyway. So yes, Los Blancos would undoubtedly have liked to have seen him in white sooner. Still, given they kept winning and saved some cash along the way, it's hard to complain.

And that's where the good vibes end. Yes, it stands to reason that taking the best player in the world and throwing him into the current European champions probably brings about success. Mbappe means goals, and Madrid will score a lot of them - in theory.

Unfortunately, football doesn't always work like that. Of course, good players tend to make teams better. But Los Blancos have managed to sign the best player available at the position in which they are strongest. Vincius Jr, if the voters do as expected, will likely win this year's Ballon d'Or. By some measures, he was more impressive than Mbappe last season. It just so happens that the two play exactly the same position. Mbappe might be more of an inside forward than a natural left winger, but it does little to change the fact that both are left-sided attackers who cut onto their right foot. There isn't room for one of them to play left wing, while another one tucks marginally inside. Someone is going to have to play more centrally.

Mbappe has, admittedly, done that before. He was at his best for France at the 2022 World Cup, in fact, when he played nominally as a striker. But even then, he drifted into the left half space. The same can be said of him towards the end of his PSG career when he roamed all over the left side of the pitch. Mbappe may well end up as Real's central striker, or Vinicius could be switched to the right flank. Either way, it's probably not ideal.

But perhaps the biggest issue from a tactical perspective is what happens without the ball. Madrid, for long periods last season, were at their best when they didn't have the ball. All 11 men happily dropped into something resembling a 4-4-2, and simply allowed opponents to knock it about. It was, in fact, what made Los Blancos so good. You can have the ball, but there's no chance you actually do anything with it, their tactical setup seemed to suggest.

But this wasn't always a disciplined unit. Vinicius, in particular, got away with it a bit. The winger certainly wasn't lazy, but he wasn't necessarily one to scamper all over the field. He was asked, in effect, to shade opponents to one side, but stay high up the pitch, and wait for the ball in transition.

Mbappe is worse. If Vinicius was given a lifeline due to his tactical importance, then Mbappe has never really cared. It was his lack of interest in defending that contributed to the disappointment of PSG's attacking trio which also included Lionel Messi and Neymar. It was his reluctance to run that saw France manager Didier Deschamps switch him to a central role - because Les Bleus were so often exploited down their right flank in Qatar.

It is not as simple as dubbing Mbappe lazy, but he has never been a willing runner. And with Vinicius effectively given amnesty from his defensive duties, Carlo Ancelotti will have to find a way to avoid playing 9 vs 11 at times.

More broadly, the issue with Mbappe might be how he carries himself. He has never been a modest human being - top athletes rarely are. At PSG, though, he managed to get away with it all. Mbappe was bigger than the club. He controlled narratives by himself, survived petulant outbursts on social media, and publicly bullied the institution into getting his own way. It really was remarkable to see one footballer have control over a brand so big.

And it's the kind of thing he has become used to. Mbappe seized the France armband despite being nowhere near equipped to captain the side. He led campaigns for Nike. He, in effect, bullied Neymar out of Paris. Madrid won't put up with such behaviour. There are very few clubs in football that are bigger than the players that suit up for them. Madrid are one of those. In Messi and Cristiano Ronaldo, Barcelona and Manchester United have both been consumed by two of the biggest stars in football over the last 15 years. Madrid have not - and it's unlikely that they will again.

Mbappe, then, would do well to realize that. In a dressing room full of superstars, he will have to put his head down and become one of many - rather than the sole big name.

There also remains the issue of figuring out where everyone else will have to play. It's not just a question of Vinicius and Mbappe learning how to work with each other. Mbappe's arrival will have a massive knock-on effect throughout the Madrid team. Jude Bellingham, so effective last year as a No.10 turned striker, will certainly have to drop into a deeper position. Rodrygo, already uncomfortable as a right-winger, might be dropped from the side altogether - especially if Madrid opt to play with just two forwards.

Perhaps a wholesale system change is needed. Los Blancos could switch from their 4-1-2-1-2 to a more orthodox 4-3-3. Either way, there will be sacrifices made in the front line, and further back as a result. Bellingham's presumptive transition to a central midfield role will mean Ancelotti has to bench one of his men further back.

And despite the retirement of Toni Kroos, he still has too many. These are good problems to have; Real have an embarrassment of riches to work with. Still, keeping everyone happy will be tricky, even for a manager with Ancelotti's skills.

So, the biggest star in football has walked into football's most star-studded dressing room. This isn't unchartered territory in the sport - especially not for Madrid. It was club president Florentino Perez's policy, remember, to bring in the biggest name in world football every summer - the strategy of the so-called Galactico era.

But the oft-forgotten reality of the Madrid of the early 2000s is that they actually didn't win that much. It was more complicated than the fact that there were simply too many big names, but when sacrifices had to be made, and big names had to change, problems started. There is a real chance that something similar could happen here.

Mbappe may not have the tabloid era attention of David Beckham, or play for a manager so unequipped to piece it all together. But he is certainly a destabilising force, a tactical issue and a player who might think he's too big for the club. On paper, this looks like a perfect fit - one of the game's greats has earned his dream move. The reality might not be such a blissful fairy-tale.