Chelsea may be shifting their focus in their search for a leading striker this summer. 

It has long been thought that Atletico Madrid’s Radamel Falcao was Chelsea’s leading choice to become their first-choice front man next season. But there are now reports that Jose Mourinho, who is widely believed to be close to rejoining the Blues as manager, has set his sights on Borussia Dortmund's Robert Lewandowski as his first signing.

The player is thought to be on the verge of joining Bayern Munich but Mourinho appears to be trying to throw a spanner in the works. Spanish website recently revealed claims from Bayern director Karl-Heinz Rummenigge that Lewandowski’s agent Maik Barthel had taken a call from Mourinho urging the striker to move to Chelsea.

The Daily Express follows up that story by citing reports in Germany that Mourinho has texted Lewandowski directly about a move to west London.

According to the Express, Chelsea’s interest in Lewandowski signals an end to their pursuit of Falcao. The prolific Colombian will likely be significantly more expensive than Lewandowski with Falcao having a release clause of €60 million (£51m) and unlikely to be allowed to leave for less than £40 million.

Chelsea could hold an advantage over Bayern in the race to sign Lewandowski due to Dortmund’s interest in Blues attacking midfielder Kevin de Bruyne. The young Belgian is currently on loan at Werder Bremen.

Another deal could well depend on the movements of De Bruyne, however, with the 21-year-old said to be wanted by Bayer Leverkusen on loan as part of the deal to take Andre Schurrle to Stamford Bridge.

A £20 million transfer for the Germany international is thought to be imminent, with Leverkusen general manager Wolfgang Holzhauser even suspecting that Schurrle has already agreed terms with Chelsea.

"Andre Schurrle has probably signed a pre-contract deal with Chelsea," Holzhauser said, according to Sky Sports.

"It all depends on whether we let him go. We have received a concrete offer for a fee which we are considering.

"But the price alone is not decisive. We must also have alternatives, which we don't have yet."

Holzhauser’s words intimate that his club are waiting on De Bruyne’s signing before sanctioning Schurrle’s departure, although he accepts there is strong competition from Borussia Dortmund.

"He still has a few talks to hold with Chelsea," Holzhauser added.

"It looks like there is an offer from Dortmund to sign the player for a relatively high fee.

"According to our information, Chelsea don't want to sell him but just loan him out."

It doesn’t appear that Chelsea’s attack will be bolstered this summer with the arrival of latest Ajax starlet Viktor Fischer. The 18-year-old has enjoyed a stunning breakthrough season this campaign scoring 10 goals in just 17 appearances in the Eredivisie and making his debut for Denmark.

Those feats have led to interest from some of Europe’s top clubs, reportedly including Chelsea, but Fischer does not believe he is yet ready to leave Ajax.  

"I know a lot of young players who made ​​their debut in the national team and then never really made the break through,” he explained to Dutch publication Voetbal International.

“Only when you're 25, you really show how good you are. I have accomplished nothing here. It would be arrogant if I thought I was done here.”

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