Chelsea added solidly rather than spectacularly to their squad after Jose Mourinho’s return to the club this summer. The focus was firmly on youth with the likes of Andre Schurrle and Marco van Ginkel arriving, although Mourinho also showed his liking for tried-and-tested talent with the signing of Samuel Eto’o.

The Cameroonian being targeted was understandable given that none of Chelsea’s striking options appear to have convinced Mourinho. Romelu Lukaku has since left on loan, but there will still be doubts as to whether a 32-year-old Eto’o along with Fernando Torres and Demba Ba can capitalize fully on the creative play of the array of attacking midfielders behind them.

While the fact that Chelsea failed to spend big on a striker was something of a surprise, the same can also be said about the non-arrival of a commanding midfield presence. Many pointed to the return of Michael Essien from his loan spell at Real Madrid as a reason for Mourinho’s lack of action in that area, but the fact that the Ghanaian has been left out of Chelsea’s Champions League squad suggests that the manager too realizes that Essien is now a shadow of his former monstrous self.

Chelsea also appeared to consider adding to their central defensive options this season, after Mourinho declared that he saw Branislav Ivanovic firmly as a right-back. Here are four players that may be targeted in January if any of those areas become glaring deficiencies in the first half of the season.

Daniele de Rossi (Roma)

The Italy midfielder fits the profile of what Chelsea need in their midfield almost to a tee. An influential presence and impressive both with and without the ball, De Rossi has been a stalwart for Roma for a decade. His time in the Italian capital looked likely to come to an end this summer, though, after a difficult season last term. Chelsea were heavily linked for much of the off season, however it appears that the 30-year-old has resolved to stay put in the last few weeks as he rejected interest from Manchester United. Still, it is not unfeasible to think that the situation could change and De Rossi would have the attraction of not being cup-tied for the Champions League.

Nemanja Matic (Benfica)

Matic has excelled since leaving Chelsea and moving to Benfica in 2011 and was strongly linked with a return to Stamford Bridge this summer. Those stories have not gone away, with the Daily Mail claiming on Tuesday that Mourinho will watch the midfielder in action for Serbia in Friday’s World Cup qualifier against Croatia. The 25-year-old claimed that he would like to remain in Lisbon for at least one more season. The fact that he would almost certainly be unavailable for Chelsea in the Champions League makes a January move unlikely.

Zlatan Ibrahimovic (Paris Saint-Germain)

Having signed one veteran forward on massive wages with whom who he’s previously worked, could Mourinho really follow it up with another in January? It seems highly improbable. Yet, there were rumors that Ibrahimovic could even have arrived before the close of the summer window following the decision to let Lukaku leave on loan. Ibrahimovic’s future at PSG certainly seemed far from certain after the club spent big to land Edinson Cavani. The two have so far shown signs of forming a fruitful partnership but Ibrahimovic’s nose could yet quickly be put out of joint if things do not go to his liking.

Eliaquim Mangala (Porto)

The 22-year-old center-back was linked with Chelsea regularly over the summer, while Manchester City are thought to have made a late approach. Mangala revealed on deadline day that he would be staying put, but demand for his services look unlikely to decrease. The main stumbling block to any move, though, is set to be Porto’s notorious tough negotiating stance. Indeed, Porto have stated that the France international will not be able to leave for less than his €50 million (£42.3m) release clause.

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