Be they player or manager, the most important free agent in the world of football at this very moment in time is none other than Pep Guardiola.
Since resigning as Barcelona coach at the end of last season, speculation linking Guardiola with a move to England has almost gone into overdrive.
Those rumours then went through the roof when Chelsea sensationally sacked Roberto Di Matteo just six months after the Italian led the club to Champions League triumph.
One theory is that the Blues, who were eliminated from the Champions League at the first hurdle, sacked Di Matteo so they could get the run on Manchester City for the signature of Guardiola.
Like their London-based counterparts, Manchester City have also, quite embarrassingly, been knocked out in the group stages of the Champions League.
That elimination is then further compounded by the fact that Roberto Mancini has spent £269 million since joining the club in December 2009.
Add in the fact that the club were also eliminated at the same stage of the competition last season, having spent more than one billion pounds since 2008, and you can easily see why the Citizens and AC Milan have also been linked with Guardiola.
There is no doubting that Guardiola, who brought an unprecedented 14 trophies in four seasons, including two Champions League wins, is a fantastic manager, hence all the speculation.
Guardiola’s agent Jose Maria Orobitg heightened that speculation on November 7 when he said;
"The doors are open for them [AC Milan], just like they are open for Manchester City, Chelsea and so on.
"Pep will listen to offers and then he will evaluate them.
"But so far we haven’t talked about Milan because Guardiola won’t be coaching until next season."
It is believed that Massimo Allegri, AC Milan's manager, is under all kinds of pressure after a poor start to the season, which has seen the Rossoneri plummet to 12th in Serie A.
The very fact that Orobtig name-checked Manchester City is significant because it shows that the Premier League champions are at the foremost in his thoughts.
For Roberto Mancini, it could be bad news.
Having overseen two embarrassing Champions League exits in a row it is little wonder that Guardiola has been linked with the club.
Those links, however, are not without foundation.
When Roberto Mancini began to wage his Rafael Benitez/Rick Parry style feud with Brian Marwood during the summer, little could he have known that he may have started the process to his eventual sacking.
As a result of the feud, the City board moved very quickly by moving Brian Marwood to one side as managing director of the club's football academy.
But, and most significantly, they then replaced him with a man of real football stature.
By giving Marwood's old role to Txiki Begiristain the City board have sent out a real message to Mancini—your job is in matters on the pitch.
The added incentive to Mancini to stay focused on on-field matters in Begiristain's past.
Before City, the ex-Spanish international was sporting director at Barcelona and worked in a daily basis and mentored the now out-of-work Pep Guardiola.
With the three aforementioned clubs linked with Guardiola, one must wonder why he would be interested in becoming the latest Chelsea or AC Milan manager over Manchester City?
The shadow lurking in the back during all these public negotiations are Barcelona.
The Spanish giants know that Guardiola is interested in City and would be mad not to be terrified at the prospect.
Pep and Begiristain both know the set-up at Barca intimately and with City's resources they would be in a position to poach players, a-la Arsenal, and then go about setting up a club in its image.
They could yet offer him a backstage stage role to stop that very prospect.
The other interested parties are, Chelsea who have gone through nine managers since 2004 and AC Milan have only gone through three in the same period and have very little money to spend.
Leaving City in pole position.
Since taking over in 2008, Mansour bin Zayed Al Nahyan and the Abu Dhabi United Group have been more than patient with Mark Hughes and Roberto Mancini and have allowed them to spend vast amounts.
Given the choice between the three clubs which would you choose if you were Guardiola?