Chelsea Transfer News: Oscar de Marcos Targeted, Latest Blues Rumours

Chelsea are reportedly eyeing Athletic Bilbao star Oscar de Marcos as a possible addition during the summer transfer window.

That's according to the Sun's Alan Nixon, who claims the Blues sent “spies” to watch the 26-year-old during Bilbao's UEFA Europa League clash with Valencia. The report goes on to say Manchester United wanted to buy him several years ago but baulked at Athletic's asking price.

Per Nixon, he is currently rated at £20 million, and some regard him as an ideal replacement for Ramires, who left the club for China during the winter transfer window. The report even compares him to Roy Keane, which is odd, considering the Spain international is primarily a right-back who occasionally plays as a winger.

Here's a look at some of his highlights:

De Marcos is but the latest in a long line of star Spanish full-backs, but unlike several of his compatriots, he has largely flown under the radar. This can partly be explained by the fact he plays for Athletic, a club that generally doesn't get that much publicity outside of Spain.

The Basques have a Cantera policy, which means only Basque players are allowed to play for Athletic. As a result, they're notoriously difficult to negotiate with, as they will squeeze prospective buyers for every penny, knowing how difficult it is to replace their stars.

Foreign clubs know this and generally only deal with Athletic unless a talent is too good to pass up, and it's become impossible to ignore De Marcos' strong play over the years. Per Bleacher Report's Karl Matchett, he has also played a role in Bilbao's recent resurgence, after the Basques suffered through an inconsistent start to the season:

Like most modern full-backs, De Marcos is a strong crosser who likes to get forward early and often, and he has all of the physical tools to do so. Per WhoScored.com, he's played as a winger this season, and that kind of versatility only adds to his value.

What separates him from a lot of other full-backs are his defensive contributions, however. Per WhoScored, he's averaging almost three tackles and three interceptions per La Liga match this season, and his tackling numbers are even higher in the Europa League.

Those are some impressive numbers that explain why a club like Chelsea might be interested. Branislav Ivanovic isn't enjoying a particularly fine season, and Chelsea's defensive depth has been tested in 2015-16. De Marcos brings incredible positional versatility to the table, and even as a depth option, he could be a worthwhile investment.

As shared by Inside Athletic Club, he rarely misses time through injury, and he's as dependable as they come. There aren't too many 26-year-olds who have already clocked 200 La Liga appearances:

The valuation of £20 million is steep, but knowing Athletic, De Marcos likely won't be available for anything less.

Spurs Want Jonathan Calleri

Andre Penner/Associated Press

Neil Moxley of the Sunday People (h/t Metro's Tom Olver) claims Tottenham Hotspur boss Mauricio Pochettino has put Sao Paulo striker Jonathan Calleri at the top of his wish list. Olver writes that both Chelsea and Arsenal are also eyeing the Argentinian.

Many have long touted the 22-year-old former Boca Juniors player as a rising star and future great, but he's yet to make the step up to European competition. Deportivo Maldonado, an Uruguayan club, currently own him, though they loaned him to Sao Paulo.

Here's a look at some of his highlights:

Per Moxley, Calleri will receive an Italian passport this summer, which should simplify a Premier League move, as it would bypass the need for a work permit for players from outside Europe.

Calleri is a promising prospect who has impressed with his unselfishness in front of goal and work rate. He reads the game exceptionally well and is at his best in open space, where he can use his pace to shake off defenders and either find open team-mates or finish chances himself.

Per Moxley, Calleri is seen as a cheaper alternative to Lyon's Alexandre Lacazette by Pochettino, but you have to think Chelsea will aim higher when they enter the summer market. The new manager will want to add at least one or two bonafide stars, so expect the Blues to chase bigger names than Calleri.

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