Jose Mourinho's Chelsea side lie just two points off the top of the Premier League, despite having failed to find top form thus far this season.
Heading into the second half of the season, they are perfectly positioned to kick on and claim title success. However, in order to do so, Mourinho will be keen to strengthen his resources in the January transfer window—despite his comments in a press conference just a fortnight ago:
Chelsea's strikers Samuel Eto'o, Fernando Torres and Demba Ba have amassed just five league goals between them this campaign in what would appear to be the position most likely to be strengthened.
Despite the club's considerable creative talents in midfield, they are not performing to expected standards and Mourinho is not known for accepting second best from his players. Add in a lack of strength at the base of midfield and it would seem highly unlikely that the club will remain inactive over the winter.
But who will the Blues be targeting in the weeks ahead?
Diego Costa (Atletico Madrid)
Per the Daily Star's Nick Lustig, Chelsea are preparing a January offer for Atletico Madrid forward Diego Costa. The scorer of 19 league goals already this La Liga season, Costa is one of European football's hottest properties at the present time.
There will be difficulties in securing his signature, though. Atletico are level with Barcelona at the top of La Liga, and the potential revenue from any success or long European run would have to be factored into any negotiation. Quite simply, only an enormous offer would even be considered.
Chelsea would be a much better side with a player of Costa's quality and determination leading the line, and it would be no surprise to see them at least make an attempt for his capture. They may, though, be forced to wait until the summer for any real progress.
Eliaquim Mangala (Porto)
Since signing for the Portuguese giants from Standard Liege in 2011, Mangala's progress to become regarded as one of European football's best young centre-backs has been rapid.
With David Luiz out of favour under Mourinho and John Terry well into the twilight of his career, a central defensive alternative is a priority for the Blues over coming months. Whether they wait until the summer to strengthen or move for new recruits in January, though, remains unclear.
Goal.com's Johann Crochet reported this week that the Frenchman believes he can fulfill his World Cup ambitions at Porto, which could hinder any Chelsea approach. Should an offer arrive for Luiz, though, the Blues may have no option but to persuade Mangala to bring forward his Porto exit plans.
Fredy Guarin (Inter)
Colombian midfielder Guarin has shot to the top of the Blues' transfer agenda of late, with the player himself confirming negotiations with Chelsea per the Mirror's Alex Richards.
While Guarin has played as a powerful No. 10 during his time in Italy, it would seem most likely that he would revert to the deeper midfield role in which he became famous should he move to Stamford Bridge. With his strength and technical ability, he would be ideal alongside Ramires as a pivot or in a three-man midfield.
The most likely of Chelsea's transfer targets to make the switch in January, with a deal already in the works, Guarin has never played under Mourinho despite their shared connections with Porto and Inter Milan, but he spent time under former Mourinho protege Andre Villas-Boas.
Nemanja Matic (Benfica)
Should Guarin fail to complete a move to West London, then suggestions are that the Blues would return for former player Matic, who has a €40 million release clause in his contract per the Express' Ben Jefferson.
Matic spent time at Chelsea previously, having moved to Portugal as part of the deal which saw David Luiz move to West London in 2011.
Having excelled in Portugal, though, he is now on the radar of many of Europe's best clubs as a potential midfield recruit, and it would appear that the Blues are among those tracking his progress.
Per Sky Sports, Benfica admitted last summer it would be difficult to retain Matic, and that situation is unlikely to have changed heading into January.