Diego Costa has completed a medical at Chelsea, ahead of his proposed £32 million transfer from Atletico Madrid. The Brazilian-born striker, who is still recovering from a hamstring injury, took time out from preparing for the World Cup with Spain to put the final touches on the deal after Chelsea are thought to have met his €40 million buyout clause.

The transfer completes manager Jose Mourinho’s search for a top quality striker to lead his attack. After failing in a move for Wayne Rooney last summer, he brought in Samuel Eto’o on a one-year deal. But, between them, Eto’o, Fernando Torres and Demba Ba only managed 19 Premier League goals as Chelsea finished third. Diego Costa struck 36 goals in all competitions. Torres could yet replace Costa at Atletico Madrid, freeing up more salary space for Mourinho to further add to his squad following the sale of David Luiz which could recoup as much as £50 million in transfer fees.

Costa may not be the only Atletico player to arrive at Stamford Bridge this summer. Left-back Filipe Luis has been strongly linked as a candidate to replace the departing Ashley Cole, while Portuguese midfielder Tiago could return to the club he played for between 2004-05 on a free transfer to fill the void left by Frank Lampard.

According to The Independent, fellow Atletico midfielder Koke is also admired by Mourinho. The 22-year-old, a member of Spain’s World Cup squad, provided 15 assists last season and combined them with the type of defensive discipline that will appeal to Mourinho. Chelsea would face a battle from Barcelona to secure his signature, however, with the Catalan club thought to be chasing Koke to replace Cesc Fabregas. Koke has revealed that, though aware of Barcelona’s interest, he intends to stay at the Spanish champions.

“Barcelona is one of the best teams in the world and that they are interested in you means that you must be doing something right. That is very nice for a footballer,” he told Marca, according to Sky Sports. "In any case, I only think about keeping working. I want to stay here and everyone knows it. I see myself at Atletico next season."”

Further complicating the situation for Mourinho is the fact that, according to The Independent, Chelsea’s hierarchy are keen to sign Fabregas. Mourinho is said to be far less enthusiastic to capture a player who has failed to hold down a regular role in the side during his three years at Barcelona. More forward-thinking than Koke, it is difficult to see Fabregas fitting into Mourinho’s deep central midfield two or as the central attacking midfielder, where Oscar is a favorite of the coach. Following Mourinho’s time in charge of Real Madrid, the duo’s frosty relationship would also have to be overcome.

Paul Pogba is another midfielder widely said to be under consideration. With his dynamism and physicality, it is certainly easy to see the former Manchester United youngster flourishing under Mourinho. The 21-year-old will, though, be expensive to prize away from Italian champions Juventus, while Real Madrid and Paris Saint-Germain have also been strongly linked.