Mauricio Pochettino has previously managed Espanyol, Southampton, Tottenham and Paris St-Germain
Mauricio Pochettino's appointment as Chelsea manager may come to be viewed as the defining moment of the post-Roman Abramovich era.
To say the first 12 months of co-owners Todd Boehly and Behdad Eghbali have been underwhelming - and underwhelming to the tune of £600m - would be a masterpiece of understatement.
The Clearlake group marked their 100th day in charge by sacking Chelsea's Champions League-winning manager Thomas Tuchel while the promises of long-term faith and a time-honoured project under successor Graham Potter lasted 31 games.
In that time, Chelsea have torched vast sums of transfer cash without any apparent strategy or structure, acquisitions seemingly made on a whim or at the first sign of interest from Premier League rivals, with the spree accompanied by a failure to sign a striker who can score goals.
Club legend Frank Lampard has conducted a less-than-successful holding operation in which they went out of the Champions League to Real Madrid and suffered top-flight losses that left them lurching in mid-table and out of European competition.
Not that this should be laid at Lampard's door. The damage was already done. The bounce of his return was a flatline.
Goodwill has also been evaporating, with Boehly a target for angry fans, while his dressing-room visit after the loss to Brighton last month - in which he labelled the season "embarrassing" - was a hindrance rather than a help, demonstrating a lack of self-awareness.
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Yes, Chelsea's season has been embarrassing but Boehly has more than played his part in that.
And this is why Pochettino's appointment means so much to Chelsea, Boehly and his cohorts.
The law of averages suggests, after getting so many decisions wrong, they are scheduled to get one right and must hope the arrival of the highly regarded former Spurs manager is exactly that.
Boehly will hope it is third time lucky with Chelsea managers because, with Arsenal and Newcastle very much part of the equation at the top end of the table now, there are new battles to go beside the old rivalries with Liverpool, Manchester City and Manchester United. Tottenham, for all their recent troubles, will also have hopes of improvement under their next manager.
Chelsea, so long in pursuit of the big prizes both at home and in Europe, cannot afford to fall further behind given the stakes are so high following their financial outlay.
It has been said before, but this is one decision that must land on target.
And in Pochettino, if he is given the right conditions, Boehly may just have the man to at least fashion the vast band of new players who have arrived in west London into something resembling a shape.
The Argentine has a fine reputation in England from his work at Spurs and is charismatic enough to ensure the large majority of Chelsea fans will not only set aside his previous connections with their rivals but welcome him.
Many Spurs fans wanted their former boss - who was sacked by Daniel Levy in November 2019, six months after reaching the Champions League final - back in north London, but that has never been on the cards.
Pochettino, whose high pressing and attractive style of play has always won plaudits, will also want to prove he can win trophies in England after securing the Ligue 1 title and French Cup during his spell at Paris St-Germain.
This was always the question placed against Pochettino at Spurs. He made them contenders but could never make them winners. Chelsea will not be satisfied with that and nor, it should be stressed, will he.
Pochettino led Spurs to the Champions League final for the first time
Chelsea and Boehly need their new manager to work fast after a dreadful season that posed justifiable questions about the owners' competence and knowledge of how football works.
Pochettino looks the perfect fit and will benefit from the fact he joins with the bar having been set so low - the usual sky-high expectations at Chelsea diluted, for now at least, by their painful fall from grace.
He has a personality and man-management skills that make players warm to him, especially young players who revel under his guidance, while he also renewed the Spurs squad after succeeding Tim Sherwood in May 2014.
This should not be mistaken for a lack of ruthlessness, as Chelsea's players will find out if they do not meet the demands, both in the footballing and physical context, of Pochettino and his trusted assistant Jesus Perez.
Chelsea can also be confident he will have none of the credibility problems, unfair or otherwise, that provided a backdrop to Potter's tenure, when the Englishman failed to convince supporters he was the right profile to manage this dysfunctional giant of a club having arrived from Brighton.
Boehly would do well to listen to Pochettino's Premier League experiences and be guided by his manager given the ownership's own theories have been shot to pieces by the evidence of their first campaign at the helm.
For all the scattergun nature of Chelsea's transfer spree, during which a Frankenstein's monster of a squad has been assembled, good players have undoubtedly arrived such as £107m Argentina World Cup winner Enzo Fernandez - and there are raw materials to work with.
Pochettino has proved adept in that, but now Boehly and co must step back and let Pochettino make those key decisions on who stays, who goes, and who arrives. He also has reserves of home-grown talent to work with, which he will relish.
It is time for Chelsea's owners to reduce their profile.
And if their decision to bring in Pochettino, fuelled and motivated by his time away, is a success it might just help them achieve that.
One thing is certain - Chelsea's owners cannot afford another failure.
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Source: bbc.com