Chelsea have gone from ruthless to toothless.

English football's most clinical winners have scored one goal in four league games and began their defeat by Bournemouth with a makeshift striker, in Eden Hazard, who has not struck for them since May.

The Belgian was thrust forward following the fallout between Diego Costa and Jose Mourinho but while the Spaniard was summoned as a substitute on Saturday, his drought continued.

Costa threw a bib towards his manager at White Hart Lane the previous week. Typically, he missed.

He has mustered just seven goals in 10 months.

Only three have come in the league this season.

Even Aston Villa, who have made the worst start in Premier League history, have as prolific a forward.

Perhaps Costa's benching for the last two games will be the short, sharp shock to spur him back into scoring form yet the sense is that the hunt for a new forward has begun.

Mourinho has said he will not spend in January.

He has also admitted that, given Chelsea's dismal form, he had no right to ask the board for further funds.

Yet, Chelsea must answer two questions.

Can they afford to spend? Can they afford not to?

Chelsea incurred a loss of £23 million (S$49 million) in their title-winning season. In the age of Financial Fair Play, it limits their room for manoeuvre.

Manchester United saw a £38 million drop in income in the season they did not compete in the Champions League, and the prize money has increased since then.

A scorer who propels Chelsea into the top four could be an insurance policy against such a deficit.

One who does not could be a case of a failing club chasing their losses.

Mourinho is not averse to January trading.

He has bought in each of the last two winter windows, with two successes - Nemanja Matic and Kurt Zouma - and two failures, Mohamed Salah and Juan Cuadrado. Yet, none was charged with supplying the immediate impact Chelsea need now.

Their task is doubly difficult.

There are comparatively few world-class strikers and they are rarely available in January.

A dream addition would be Gonzalo Higuain, Napoli's top scorer in Serie A and a forward with the physicality and finishing to suit Mourinho's tactics.

Antoine Griezmann is a mooted target and Chelsea have long relationships with both Atletico Madrid and agent Jorge Mendes, but the Frenchman is not an out-and-out target man.

Mourinho tends to prefer a forward such as Costa or Didier Drogba who can play with his back to goal and hold the ball up.

Griezmann has more in common with Hazard.

Each would be an expensive, and perhaps unobtainable option. Napoli, after all, are genuine title contenders like Atletico.

Shakhtar Donetsk's prolific Alex Teixeira may be the most attainable, in-form recruit abroad.

The English alternatives will not come cheap - English players rarely do - but may be more willing.

Saido Berahino agitated for a £25 million move to Tottenham in the summer and is not in the West Bromwich Albion team.

Jamie Vardy's fortunes are at the polar opposite.

The Premier League's top scorer has the form and momentum Costa lacks and this may be his best chance to secure a move to an elite club.

Yet, while both have pace, neither is a conventional Mourinho front man.

Then, there are the aged options, potential short-term fixes.

Emmanuel Adebayor, who is unattached, is not a long-term bet for anyone but did a four-month job for Mourinho at Real Madrid. Robin van Persie may relish a switch away from Fenerbahce but seems in decline.

Such a move may reek of desperation, although not as much as loaning the wretched Radamel Falcao, but desperate times could call for desperate measures.