However, the interim manager has rescued a season, which threatened to spiral downwards on the back of an early Champions League exit, from potential calamity.
The Spaniard replaced club legend Roberto Di Matteo at the helm in November after the Italian was dismissed by Chelsea owner Roman Abramovich following a 3-0 defeat to Juventus, which left the team's defence of the Champions League in tatters.
Benitez's presence in the dugout for his first game in charge was greeted with jeers from a sizable portion of the Stamford Bridge crowd ahead of the draw with Manchester City.
Chelsea Supporters Group chair Trizia Fiorellino told Radio 5 Live after the appointment that "Benitez is a poor manager" and fans revealed their disdain for the short-term boss with a series of banners at Stamford Bridge (Daily Mail).
Chelsea pulled the rug from under Roberto Di Matteo, which was just ludicrous. Now they have got in someone of Benitez’s calibre. He is a poor manager. Nobody has wanted to employ him for two years. What does that tell you? He is the wrong choice for Chelsea and the fans do not want him.
The Real Madrid coach is, understandably, a legendary figure for Chelsea supporters, and the emergence of the Portuguese manager as a possible successor to Benitez this summer has left the supporters salivating.
Unfortunately for Benitez, Mourinho used his post-Champions League defeat to Borussia Dortmund to hint further at a Chelsea return (ESPN), just 48 hours before the Spaniard guided the West London side into the Europa League Final at the expense of Basel.
Such is the nature of Mourinho's simmering feud with Benitez that it is not inconceivable to consider the former Inter Milan manager knew exactly what he was doing. But it is hoped that the Chelsea legend has too much respect for Blues fans than to play with their feelings merely to undermine Benitez.
After Chelsea defeated Middlesbrough in the FA Cup quarterfinal in February, Benitez voiced his opinion on the supporters' disregard for him (Daily Telegraph) and assured them his time at Stamford Bridge would end in the summer.
Since then, however, Benitez has guided Chelsea into the Europa League Final and will ensure Champions League football for his successor with a home win over Tottenham in the Premier League on Wednesday.
Perhaps more importantly, Benitez has overseen two defeats of Manchester United in the league and the FA Cup during his interim period in charge.
As Bleacher Report's Joe Krishnan highlighted, Sunday's win even provoked what previously seemed impossible: Benitez appeared to be applauded from the field by Chelsea fans at Old Trafford.
Benitez has succeeded with only the addition of Demba Ba to his squad in January while also succeeding in rotating the squad without, externally at least, appearing to upset senior playing figures at the club.
It has not been an easy time for Benitez, but he has ridden a stormy few months to keep Chelsea on track for the Champions League next season with some impressive wins while also giving the fans another European final, this time in Amsterdam against Benfica.
If Mourinho does not make his anticipated return to Chelsea, there may be regrets that some fans could not bury their differences with Benitez.