With Spain having been knocked out of the World Cup early, it’s to be expected that Diego Costa’s transfer from Atletico Madrid to Chelsea will be confirmed in the coming days.

But Jose Mourinho is looking to completely revamp his underperforming forward line this summer. Samuel Eto’o has moved on after his one-year deal expired, confirming that he’s no longer the player he once was, and either one of or both of Fernando Torres and Demba Ba will move on.

Costa may be a high-priced acquisition – and one who certainly has his doubters after his performances at the World Cup – but Chelsea will need depth next season, as well as the quality for Mourinho to be comforted in the knowledge that his squad is good enough to compete on all fronts.

With Costa to Chelsea looking as good as done, here are five strikers who could follow the Spanish international to Stamford Bridge.

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Click on Huntelaar to start the countdown

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Mario Mandzukic

Mario Mandzukic looked close to rejoining old club Wolfsburg, but that move has reportedly fallen through and the Bayern forward is still on the market.

Even before signing Diego Costa, Chelsea were chasing Mandzukic, who will move on from the current Bundesliga champions after Robert Lewandowski’s signing in January. Mandzukic is a hard worker who can be considered one of the best finishers in Europe.

His stature, versatility and ability in the air would make him a great addition to Chelsea’s squad for next season. It is easy to imagine Mandzukic thriving in Mourinho’s team in the coming seasons.

Jackson Martinez

It would make a lot of sense for Mourinho to look to his old club Porto in order to strengthen his attack ahead of next season. Jackson Martinez has been in and out of the Colombia team at the World Cup, but the striker has already scored a couple of impressive goals against Japan.

Like past strikers who came to fame in Europe through their exploits for Porto, it’s only a matter of time before Martinez himself moves on and rides the wave of two prolific seasons in front of goal.

Martinez would be a great help to Diego Costa in sharing the scoring responsibility at Stamford Bridge. It’s also difficult to see where the major compromise in quality would be when rotating between the two.

Hulk

Hulk has long been linked with a move away from Zenit and to the Premier League. The Brazil international does divide opinion, however. He’s a regular for his national team and cost Zenit £48 million when they signed him from Porto in 2012. But many aren’t convinced.

His greatest asset is clearly his shooting, which can be devastating at times, though it’s also easy to be frustrated by the forward, who can go missing in a big way during matches.

Perhaps Jose Mourinho is the manager to get the best out of Hulk, who has a fantastic scoring record backing him from his days in Portugal. As a regular on the right of Brazil’s attack, Hulk would offer Mourinho the option to use him either through the middle or on the wings at Stamford Bridge.

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Klaas-Jan Huntelaar

Klaas-Jan Huntelaar has been marginalised for much of the most recent three international tournaments with the Netherlands, but the striker showed his worth against Mexico on Sunday, assisting Wesley Sneijder for the first Dutch goal and converting from the penalty spot, which saw the Netherlands advance.

It says a lot about Huntelaar’s class that he’s been able to pick up where he left off. After a long injury layoff which last almost the entire first half of last season, the Schalke forward returned to the team after the winter break and finished the season on 14 goals in 21 games. For his national team, Huntelaar had yet to be involved at this World Cup before his cameo on Sunday.

The Dutch striker may be into his thirties now, but he remains one of Europe’s best finishers. He’d add a considerable amount of depth and quality to the Chelsea squad next season.

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Romelu Lukaku

Romelu Lukaku may already be on the books at Chelsea, but there are many fans who believe he should be retained after spending the last two seasons at West Brom and Everton.

Lukaku looked to have created a sour relationship with Jose Mourinho, who certainly looks to be inclined to sell the forward at some stage this summer.

On one hands, selling Lukaku has a lot of upside due to the money that will be brought in. after his last two seasons on loan in the Premier League, there will be many clubs in England and abroad who will be enquiring after his services.

But Lukaku can also offer a lot to Chelsea. He knows the Premier League well, worked extremely hard for Roberto Martinez’s Everton last season and hits double figures for goals with ease. If the relationship between player and coach can be repaired, Lukaku could be a considerable asset to Chelsea.