As Chelsea head off for their pre-season tour of Asia, Jose Mourinho was eager to praise the virtues of his three signings since taking up the role of manager at Stamford Bridge for the second time, but that is unlikely to be the end of his transfer business in this window. The arrivals of wide forward Andre Schurrle and forward-thinking midfielder Marco van Ginkel promise to benefit Chelsea for years to come, while Mark Schwarzer will provide short-term cover for Petr Cech.

Still, there are voids that still need to be filled in Mourinho’s squad.

Chief among those is up front. Neither of the trio of Fernando Torres, Demba Ba or Romelu Lukaku convince that they can lead the line for a side looking to win the Premier League and Champions League. Torres no longer has the ability to be a difference maker at the top level, Ba never quite had that quality, while Lukaku is perhaps still a little raw to be depended on week in week out.

Mourinho appears to realize this fact, but so far his efforts to being in a renowned frontman have proved fruitless. Radamel Falcao has signed for Monaco, while Edinson Cavani may also be on the verge of being lured by the riches on offer at fellow Ligue 1 nouveau-riches Paris Saint-Germain. However, with the Napoli striker appearing to be hesitating over committing himself to the move after PSG agreed to meet his monstrous €63 million (£54.3m) release clause, there may still be hope for Chelsea.

Cavani has expressed his growing frustration with Napoli president Aurelio de Laurentiis’s refusal to consider any offers below the buyout clause. The situation will take an interesting turn if the 26-year-old refuses the move to the French capital. Chelsea are reported to have had bids knocked back for Cavani but will hope that if he takes a stand then they could be back in the running.

Cavani’s combination of power and mobility would be perfect to lead the line in a Mourinho side, which have traditionally relied on those attributes for their counter-attacking style. Another good fit and a potentially far more cost-efficient one would be Borussia Dortmund’s Robert Lewandowski. The Poland international is perhaps the best traditional number nine in the world right now, with his ability to be able to create something out of nothing in the box, exceptional capacity to bring others into the game and a strong work rate.

Thus far Dortmund have refused to allow Lewandowski his desired move to rivals Bayern Munich and have also said that he won’t be going anywhere this summer, despite the player having just a year left on his contract. It remains to be seen, though, if Dortmund will be so resolute if a club like Chelsea put a massive offer on their table.

While Oriol Romeu should return from injury and Michael Essien has returned from a loan spell at Real Madrid, Chelsea still lack an authoritative presence at the base of their midfield. To fulfill that need, it appears that Mourinho is attempting to finally lure a player whom he has long been an admirer of in Roma’s Daniele de Rossi. A one-club man, there are signs that the Italy international may be coming to the end of his time in the Italian capital.

The 29-year-old would bring a positive influence to the side, while he is strongly equipped both with and without the ball. If Chelsea can secure him at a reasonable price, it could prove some of the shrewdest business in the Premier League’s summer window.

At the other end of the age scale, there have also been rumors of Chelsea’s interest in Geoffrey Kondogbia. The 20-year-old impressed in his debut season with Sevilla last term and is further enhancing his reputation in helping France to the final of the Under-20 World Cup. Although still raw and needing to improve his range of passing, the left-footed Kondogbia is an imposing physical presence and can also drive forward with the ball in a manner that has predictably earned him comparisons with Patrick Vieira.  

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