From the ill-timed sacking of assistant coach Ray Wilkins to Didier Drogba's battle with malaria to the departure of seasoned veterans like Michael Ballack and Ricardo Carvalho... there's been no shortage of theories explaining Chelsea's fall from grace this season.
Even after a spirited 2-1 home victory over leaders Manchester United midweek, the Blues lie in fourth position, 12 points off the pace with 11 games left, giving them virtually no chance of retaining their Premier League title.
But according to Gianfranco Zola, the man once voted the club's greatest ever player, one of the main reasons behind Chelsea's inability to fire this season could lie with a forgotten midfielder who has played just three first team games.
Yossi Benayoun is on the long road back to fitness after rupturing his Achilles tendon in September during a Carling Cup game against Newcastle United. The Israeli international had joined the club only two months earlier from Liverpool in a GBP5.5millon deal.
'They really miss Benayoun, who, in my opinion, was a very influential player,' Zola said. 'He was brought in to bring something different to the club, a little spark. He was someone for the last 25 minutes who could create something... something Zola-like maybe.'
The former Italy international smiles with a hint of embarrassment as he mentions his own name in the context of the current squad. Even though he was the talisman as Chelsea won five trophies in the late 1990s, the modest 44-year-old seems reluctant to beat his own drum.