There is a hole at Real Madrid that has never been filled, properly, and John Obi Mikel is the man for the job.
Claude Makelele left Los Blancos to join Chelsea in 2003 and since then a variety of midfielders, from Thomas Gravesen to Lassana Diarra, Fernando Gago to Asier Illarramendi have tried and failed to replace him.
Xabi Alonso changed the mould and paved the way for someone like Luka Modric to play in defensive midfield, an extremely attacking, creative player for the position.
Modric is doing an excellent job, and Toni Kroos alongside him too.
However, in some games, Madrid lack the presence of a true defensive midfielder, someone whose first thought, their natural instinct, is to shut down the opposition.
Against Celta Vigo Madrid had huge holes in their midfield; they were being ripped to pieces.
Modric was missing, out injured, but even he wouldn't have been able to fill that space like Mikel would.
His vision, strength and ability to shield the ball with three or more opposition players trying to take it from him is a valuable resource.
And per Tuttomercatoweb, h/t Sport, Carlo Ancelotti may be lining up a move for the Chelsea man.
Every manager Mikel has ever had at Chelsea has appreciated him.
Jose Mourinho helped him become the defensive midfielder he is today, after signing him in 2006.
At just 19 years old, Mourinho played Mikel 42 times in his debut season in English football.
There were rash challenges and a steep learning curve for the Nigerian, but he's managed it and hasn't been sent off since the 2007-08 season.
After Mourinho, Avram Grant. After Grant, Luiz Felipe Scolari. Guus Hiddink, Ancelotti himself, Andre Villas-Boas, Roberto Di Matteo, Rafa Benitez. Mikel has been appreciated by all of these managers.
While Chelsea fans have been left divided, with some unable to countenance the fact a midfielder who rarely scores or assists has been such an important part of the team, until this season Mikel has been integral.
He is a big-game player. When Chelsea need him to step up and take the weight, he has done.
Arguably his best performance for the club came in the 2012 Champions League final against Bayern Munich. A resolute display at the heart of the team kept the Germans at bay, and Chelsea eventually emerged triumphant.
Ancelotti used Mikel a lot in the season he won the double with Chelsea, the midfielder being the platform that Florent Malouda, Didier Drogba, Frank Lampard, Nicholas Anelka and Co built from.
This season Mikel has missed out on many games through injury, and also because Nemanja Matic has been imperious in defensive midfield.
The Serb isn't going anywhere and, at 28, Mikel will want to play more while he is in his pomp, meaning he would be open to moving to Madrid.
One problem is Florentino Perez. He was the reason Makelele left in the first place. Per the Daily Mail, the Madrid president said:
His technique is average, he lacks the speed and skill to take the ball past opponents and 90 per cent of his distribution either goes backwards or sideways. Younger players will arrive who will cause Makelele to be forgotten.
If that's what he thinks about Makelele, then he is in for an unpleasant surprise if Mikel signs in the summer.
But after Makelele left, things fell apart at Real Madrid. When Makalele left Chelsea, Mikel was there to replace him.
Mikel might never reach the Frenchman's level, but there is no shame in that. The "water-carrier" was a genius, even if it took a while for people to appreciate it.
Illarramendi seems likely to leave in the summer. Lucas Silva was signed but doesn't look ready yet. Casemiro is doing a good job at Porto on loan, but it's hard to envisage a future for him as part of the team.
If Mikel arrives at Madrid, Ancelotti knows he has a pair of hands he can trust.
A player to stick in the midfield when Real Madrid need to solidify, perfect for away trips to places like the Mestalla, Balaidos, El Madrigal and, yes, the Camp Nou.
Just don't rely on him to score a goal.