Costa, whose injury caused him to writhe in agony on the pitch during the Blues' 3-3 draw with Everton, mercifully has no broken bones. But he does have a bruised shin – something likely to linger, and cause him much pain over the next week or two.

He seems unlikely, at this stage, to feature at Arsenal on Sunday afternoon, raising the question of just who Guus Hiddink will pitch into the game against the Gunners.

Premier League Chelsea's season on a knife edge 16/01/2016 AT 21:29

Loic Remy, who has not started a game since September, and has not managed a full 90 minutes in the Premier League in over a year, is the favourite.

He had very little impact after his 80th minute replacement of Costa against the Toffees, and has had an 18-month stint at Chelsea where first-team exposure has been minimal.

Behind him in the pecking order is Radamel Falcao – whose latest, unexplained injury was described at the weekend as “very serious” by Hiddink.

He didn't look like a pro suffering from a major calamity as he chatted amiably with a colleague in the Stamford Bridge press room last Wednesday night – grinning widely, as he stood by the tunnel door. But the stand-in boss says it will be at least eight weeks before he is seen in action again – and one has to wonder if even that is an ambitious prediction for the £250,000-a week striker.

Beyond that, we're into the realms of fantasy.

Patrick Bamford, recalled from a fruitless loan at Crystal Palace, seems unlikely to ever break through at Chelsea, and is being talked of as a possible loanee to a number of Championship clubs – QPR being a possibility. There, the departure of Charlie Austin has created a vacancy: though his £4m move to Southampton has, in itself, raised eyebrows at Stamford Bridge.

There is a lack of comprehension why a player who scored 18 Premier League goals last campaign, and was rated by his club as being worth £15m as recently as the summer, was not picked up for relative pennies by the Blues. To put it into context, his transfer fee was marginally more than what Chelsea paid for Papy Djilobodji on deadline day; and £10m less than the initial fee for Baba Rahman – neither of whom has exactly created waves in west London.

Talk, at present, concentrates on Alexandre Pato – a man whose move to Chelsea was being written about back when he was still a boy, but whose career has failed to deliver the promise many had hoped.

Alexandre Pato Image credit: Reuters

Whatever, it seems unlikely anyone will arrive in time to make any real impact at the Emirates, and that Chelsea will take the trip up the Piccadilly Line with no real striker capable of amassing 90 minutes game time against the league leaders.

Chelsea's transfer policy does, at the moment, appear to have lost its way.

Their last three signings – Djilobodji, Rahman, and the loaned-back Reading defender Michael Hector – seem unlikely to ever make any form of name for themselves at the club, and all look like investments based upon some dubious hope for financial return. The story behind Rahman, in particular, which involves a telephoned recommendation from his Ghanaian international boss Avram Grant, does raise a few alarm bells about who is actually spending Chelsea's money right now.

And so, back to Arsenal and those forward-line problems. Do Chelsea go with a false-nine again, in a bid to avoid defeat rather than win a vital three points? That possibility looks, at some stage in the game, a relative certainty.

All of this highlights the fact that Chelsea have big problems at the moment, and many of those don't simply come to an end when the referee blows his whistle for full time.

Football Martinez, social media rage at Terry’s equaliser for Chelsea 16/01/2016 AT 16:29