He will reportedly earn £4.6 million a year.
Mark my words, Cahill will be a regrettable decision, and I dare André Villas-Boas to play Cahill and John Terry in a high line against Napoli.
This article will tell you why Cahill is a bad signing and will list nine of the most regrettable Chelsea signings in recent memory.
Fact: Nani, David Silva and Luis Suárez have made more tackles than Gary Cahill.
Fact: Cahill completes only 74.4 percent of his passes—below par for a defender.
It's laughable how some people can claim centre-backs don't need to make tackles.
You're a defender so you have to tackle.
The fact of the matter is Cahill has led Bolton Wanderers to the joint worst defence in the league.
I also loathe his character.
If he had the heart of a champion, he would stay at Bolton and fight to the end, like Scott Parker with West Ham United.
Instead Cahill not only forced a move away from a struggling club, but he had the audacity to hold Chelsea to a king's ransom.
Who does he think he is? Mats Hummels?
Gabriele Ambrosetti was hailed as the ''Italian Ryan Giggs.''
Unfortunately for Chelsea, Giggs had more talent in his right foot than Ambrosetti had in his entire body.
Ambrosetti along with Andrea Silenzi, Corrado Grabbi and Michele Padovano shattered the perception that Serie A footballers were superior to Premier League footballers.
Slaviša Jokanović was a joke of a signing.
Claudio Ranieri bought a deteriorating Jokanović and the tinkerman would have been better off keeping Dennis Wise or Gus Poyet.
When Jokanović was released by Chelsea, instead of pointing fingers, he owned up:
"It's true I was a regular and played a lot of games last season, but I know I played well in some matches and not so well in others.I was too inconsistent.The fans must know I tried to play well every time I played.I'm sorry, but I always tried."
You'd think that if Ian Porterfield was going to spend a then-club record £2.1 million, that he'd buy a forward who could score goals.
Robert Fleck's return of eight goals in 48 games was a factor in Porterfield becoming the first Premier League manager to be sacked.
In hindsight, Mateja Kežman should never have left PSV Eindhoven, and Chelsea should have paid attention to Luc Nilis, Jari Litmanen and Pierre van Hooijdonk not being successful in England.
For someone so talented, Kežman did not have the mentality to succeed, because as soon as defenders stuck to him instead of giving him space—he froze.
Adrian Mutu was talented enough to wage a cold war with José Mourinho, but the Romanian was foolish enough to believe he could strong-arm Mourinho whilst smoking, drinking and taking cocaine.
As soon as Mutu and cocaine became inseparable, not only was Mourinho right again, but it was a waste of £15.8 million for Chelsea.
Chris Sutton had scored four goals in 20 games for Blackburn Rovers, yet Chelsea saw fit to sign him for £10 million.
They were banking on his two 20-goal season hauls for Rovers.
Unsurprisingly, Sutton's bad form for Rovers carried over to Stamford Bridge.
Eleven years later, Chelsea signed a Liverpool forward in the same situation as Sutton, but instead of £10 million, it was £50 million.
This excellently taken photo by Clive Mason illustrates the divide between Andriy Shevchenko and José Mourinho.
At the end of the day, Shevchenko was caught in the middle of a cold war between Mourinho and Roman Abramovich.
When Shevchenko scored a beautiful goal against Tottenham Hotspur, instead of celebrating with the Ukranian, Mourinho was yelling instructions.
It was at that point, I knew Mourinho would never give Shevchenko the chance to succeed, and I began softening my harsh criticism of the Ukrainian.
Like Andriy Shevchenko, I've softened my stance on Fernando Torres, and I've become more optimistic about his chances to succeed.
Though, only if André Villas-Boas builds the team around him.
My biggest issue with Torres was the transfer fee of £50 million.
He had a Stephane Guivarc’h-esq FIFA World Cup, was having his worse season at Liverpool, and was bought during the January transfer window.
No pre-season with Chelsea, weighed down by the transfer fee, lacking confidence, looking sluggish and frozen out by Carlo Ancelotti.
No wonder Torres struggled so much.
He will start scoring goals like a £50 million valued forward if Juan Mata is played centrally.
However, Villas-Boas, who is doing his best to claim Chelsea's worst manager in recent memory, can't see what seems so blatantly obvious.
Winston Bogarde cost Chelsea £2 million per game, because he earned £8 million over four seasons, even though he only played four games.
It wasn't injury or lack of form, but his insistence on proving the importance of contractual obligations.
Chelsea didn't want him, he didn't want to play, but he did want his money.
So for four seasons, he was willing to earn £40,000 a week, just to train with the reserves.
Please read 8 Reasons Not to Sign Gary Cahill.
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