It is said that Andre Villas-Boas has to lead Chelsea to victory over two legs against Napoli to save his job, but the real factor undermining the club's season is not the shortcomings of their inexperienced manager, but the stubbornness of their senior players.
There are certain individuals at Chelsea who have served their time, but are clinging on to their status as best they can. They had success under Jose Mourinho and carried it on under Carlo Ancelotti, but they have become too powerful. I think some of them are trying to take control of a young manager.
Some of the older players know their futures could be in doubt at the end of the season as Villas-Boas could be looking to mount a purge, so will they be motivated to really push themselves and do their best for their manager? I suspect there will be around 50 per cent of the squad who will have purely selfish motivations to be honest, so I don't think the manager is getting the backing he needs.
Some of Chelsea's big names have been underperforming all season.  They are resistant to change because they fear their positions will be in jeopardy. They wouldn't be old pros if they weren't thinking that way to be honest, it's human nature, but it doesn't help the manager at all.
It is clear to me that some individuals at Chelsea wield far too much power behind the scenes. You read reports that certain players played a role in Mourinho's departure, while others may have served to undermine Luiz Felipe Scolari.
The system has remained untouched since Mourinho arrived back in 2004 and I think successive managers have been governed in what they do by players who have too much say in the matter. As a result, nothing has changed over the years and Chelsea have grown stagnant.
The club have to move on though, it's a fact. If they carry on like they are and the complexion of their squad is the same next season then they can only regress further.
Villas-Boas has taken steps towards overhauling the squad, most notably when trying to phase out Frank Lampard. They do need to wean themselves off their dependence on him and other senior players.
The way Villas-Boas wants Chelsea to play does not suit Lampard because they are trying to pass the ball more, whereas before the midfielder thrived from picking up pieces from Didier Drogba.
Chelsea brought in Juan Mata in an attempt to change their style and he started like a house on fire. However, he has been dragged back down to Chelsea's level and he needs better and mentally sharper players around him if he is to reach the standards he set at Valencia. At the moment the way Chelsea play is very pedestrian and it means they are not going to get the best out of a player like Mata.
It is a similar situation with Fernando Torres, who has now gone 21 hours without a goal. It is looking hopeless for the striker at present but Chelsea don't play to his strengths: they haven't played football since Mourinho was there and they don't pass it into midfielders or look to play intricate passes inside the centre-backs and full-backs for Torres to run onto.
Chelsea have bought themselves an Armani suit but want to carry it around in a Tesco's bag; you can't spend that kind of money on a striker and then starve him of service.
It is abundantly clear to me that Chelsea need to embrace a new culture and philosophy, but their stubborn core of aging players are preventing them from doing so. Villas-Boas needs to bring in players who actually want to play for him and take the opportunity to usher out some of the old guard in the process. Whether he is given that chance or not remains to be seen.
As for the tie that could make or break his tenure, I think Napoli will be too sharp and fluid for Chelsea and I am backing the Serie A side to progress. Chelsea drew with Birmingham at the weekend and I am sceptical about their chances of getting a result in Italy. If they are to get a draw or snatch a win they will need all the players to work hard for their team and their manager, but they don't seem inclined to do that at present.