Rafael Benitez must not only satisfy the demands of an owner who seems beyond satisfaction after taking over as Chelsea manager, he must also uncover a way to win over a sceptical fanbase.
To suggest that Benitez's arrival to succeed Roberto Di Matteo has not been received with universal acclaim by Chelsea's supporters is to offer up a masterpiece of understatement.
Benitez is a figure regarded with scepticism by many Chelsea followers following a series of epic clashes with Jose Mourinho during his time as Liverpool manager, when the Spaniard won two Champions League semi-finals in 2005 and 2007 and an FA Cup semi-final at Old Trafford in 2006.
The rivalry between Mourinho and Benitez, who also lost a League Cup final against Chelsea in 2005, grew with the passage of time and an enduring loyalty to "The Special One" means it may be an awkward introduction when he takes his place in the Stamford Bridge technical area against Manchester City on Sunday.
Indeed, on the night Di Matteo took charge of his first game as Chelsea manager in the FA Cup fifth round replay at Birmingham City last March, the travelling support spent more time chanting abuse about Benitez - who had declared his interest in the job - than backing Andre Villas-Boas's successor.
Fortunately for Benitez, Chelsea owner Roman Abramovich does not court the populist vote and sees Benitez as a solution, at least until the end of the season, to the problems that overcame Di Matteo just six months after winning the FA Cup and Champions League.
Benitez may have been sacked by Liverpool in 2010 after a six-year reign that brought one Champions League win and another losing final, plus an FA Cup triumph in 2006, but he was still receiving more glowing references from those who inhabit Anfield than those waiting to greet him at Stamford Bridge when his appointment was officially confirmed on Wednesday evening.
So Benitez will need to get off to a fast start to impress his new boss Abramovich and also to start to erase the doubts Chelsea fans clearly have about him.
He will inherit a gifted squad still in a very healthy third place in the Premier League. He will also inherit his former Liverpool striker Fernando Torres, increasingly looking lost and lonely as he tries in vain to rediscover the magic he displayed to such significant effect under his fellow countryman on so many occasions at Anfield.
Benitez stated only recently that Torres's decline was simply a matter of lost confidence. He can now put his theory to the test - and if he is proved correct it may yet be a path to the sort of longer term deal he eventually wants at Chelsea.
If he can at least start to prove that Abramovich did not simply waste £50m on a doomed vanity project by personally driving the purchase of Torres, then Benitez will be on the way to convincing the Russian he may be worth persevering with.
While a relationship between a manager who craved complete control at Liverpool and a Chelsea owner who wields power with ruthless abandon has the appearance of a marriage made in hell, they have reached a point in time where they need each other.
Benitez has not worked since being sacked by Inter Milan in December 2010 only six months after taking over from Mourinho. He has always harboured ambitions to return to Liverpool but was overlooked by their American owners when Brendan Rodgers was appointed this summer.
He wants a showcase for his beliefs and he will not get a bigger one than that presented to him by Chelsea after such a lengthy absence. And one thing is certain, Benitez will not have lost any of the cast-iron self-confidence that his methods will bring success.
He often became bogged down by politics at Liverpool, leading to uneasy relationships with successive chief executives Rick Parry and Christian Purslow as well as former owners Tom Hicks and George Gillett.
History, as well as a long list of managerial victims, will inform Benitez that he will be wise to stick strictly to football business at Chelsea.
Abramovich, meanwhile, wants Benitez the strategist to apply his tactical and meticulous approach to this talented Chelsea squad that still has the capability to challenge strongly for the title this season, even though their grip on the Champions League is almost broken.
Another intriguing aspect of this latest Chelsea reign is how Benitez applies his methods to a squad that was reshaped this summer towards the sort of "Barcelona in blue shirts" style Abramovich has always wanted to see.
It would do Benitez a gross disservice to suggest his Liverpool teams were not entertaining but his default position is getting results. Victory above all.
And given Benitez's nature, he will have spent almost every moment out of the game plotting for this moment of return.
Abramovich, as well as the Chelsea fans who may actually welcome his appointment, will hope they are bringing in the same Benitez who arrived at Liverpool to replace Gerard Houllier after breaking up the Real Madrid and Barcelona powerbase with two La Liga titles as well the Uefa Cup in 2004 at Valencia.
Benitez came to Liverpool hungry and with something to prove but his time at Anfield ended on a sour note. He remains a peculiarly divisive personality among the football community - for every Liverpool fan who did not argue with his sacking there are plenty more who would have happily welcomed him back at any point since.
Those who count themselves as Benitez disciples insist he must always take his place in any list of the world's coaching elite. Those who do not share this admiration suggest all his limitations were brutally exposed by his short reign at Inter Milan when replacing Mourinho after he won the Champions League, the Serie A title and the Italian Cup.
Benitez claimed the Club World Cup and the Italian Super Cup but his brief stay in Milan is regarded as a failure, paling in comparison to his old adversary Mourinho.
Now Benitez is back in business at another of Mourinho's old haunts with plenty to prove to both Abramovich and many Chelsea fans who will not greet his arrival with a sense of delight.