Club: Manchester United
Estimated Value: £45m
Alternative Targets: Radamel Falcao (Monaco), Diego Costa (Atletico), Gonzalo Higuain (Napoli), Alvaro Morata (Real Madrid), Mosquito (Atletico Paranaense) & Domenico Berardi (Sassuolo, on loan from Juventus)
It would be absolutely sensational if Chelsea were able to convince Manchester United to sell in January but stranger things have happened. Remember Fernando Torres? Jose Mourinho has been linked with Wayne Rooney since the summer and, amid United's struggles and the uncertainty over whether the England star will sign an extension on the remaining 18 months of his contract at Old Trafford, the striker might want to move. Chelsea are in desperate need of a goalscorer, despite Mourinho suggesting they will not sign a forward this month, and were also reported to have strong interest in Monaco's Radamel Falcao before his season-ending injury as a back-up option to Rooney. If Mata ends up at Old Trafford, don't rule it out.
Club: Inter Milan
Estimated Value: £15m
Alternative Targets: Youri Tielemans (Anderlecht) & Saul Niguez (Atletico Madrid)
Chelsea have reportedly already failed with one £13million bid for Fredy Guarin, with Inter Milan said to want an additional £2m if they are to sell a player who only signed from Porto in 2012. It has been claimed by Guarin that Mourinho has spoken to his agent, which suggests there is interest from both parties in the move. Chelsea are thought to want to improve their midfield options, as Mourinho wants to revert to his favoured 4-3-3 formation, and Guarin would be a perfect addition. His versatility to play anywhere across midfield combined with his strength, pace and long-range shooting when cutting in from the flanks have seen him linked with several of Europe's top clubs.
Estimated Value: £25m
Alternative Targets: Fabio Coentrao (Real Madrid), Alberto Moreno (Sevilla), Ricardo Rodriguez (Wolfsburg) & Layvin Kurzawa (Monaco)
The fees being reported as Southampton's value for 18-year-old Luke Shaw are astronomical for a teenager. Indeed, the most recent stories suggest the St Mary's club would even ask for as much as £30million, which would make the England Under 21 international the most expensive left-back in the world. Manchester City have also been linked with Shaw but Chelsea have long been considered the favourites for the signing as they look for a young successor to Ashley Cole. Ryan Bertrand could be a makeweight in any deal to take Shaw to Stamford Bridge having fallen almost completely out of the thoughts of Mourinho. Fabio Coentrao is another potential target for Chelsea but the Real Madrid man does not have age and potential on his side and is has strongly been linked to join Manchester United.
Club: Saint Etienne
Estimated Value: £10m
Alternative Targets: Eder Alvarez Balanta (River Plate)
Inter Milan and Monaco are also rumoured to want highly-rated St Etienne centre-back Kurt Zouma, who has played for France's Under 21 side. Newcastle, and their French contingent, have likewise been linked with the teenager but Chelsea seem to have the strongest interest. Any move may not materialise until the summer but it would appear Mourinho is in the January market for cover and long-term replacements for John Terry and Gary Cahill while David Luiz's future is far from certain. A note of caution for Chelsea will be that Zouma demonstrated his reckless side in getting banned for 10 games last November for a wild challenge on Sochaux midfielder Thomas Guerbert. Zouma, though, said last summer he was "happy" to be linked with Chelsea, which offers the Premier League giants great encouragement.