Maybe it was Roman Abramovich's instruction to the players to improve.
One glance at the Chelsea owner's Wikipedia page would no doubt encourage anyone to shift up a gear when told.
Perhaps it was the dismissal of Andre Villas-Boas, who paid the price for trying to move on the old guard. Or the increasingly successful interim appointment of former West Bromwich discard Roberto di Matteo, who has registered three consecutive wins.
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