There are few top strikers in Europe more eligible for a move than Jackson Martinez.
The prolific Porto striker has a goalscoring record to rival the very best, and a release clause which makes him available without the complicated negotiations.
Portuguese clubs usually place release clauses in players' contract they consider excessive, but the more Martinez continues in his current form, the more it looks good value.
After scoring 31 goals last season, the 27-year-old striker has nine goals in 11 appearance this season, signifying his debut season at Porto was no flash in the pan.
Chelsea, Arsenal, and Real Madrid have all recently been linked with a January transfer move for the Colombian over the past week.
Porto though have been attempting over the last two months to get the striker to re-negotiate his contract, but the player is stalling.
The reason for this, report Marca, is the plan of Porto president Pinto da Costa to increase Martinez' release clause to €60 million.
They write: "At the age of 27, the Colombian feels it's time to take a leap forward and that this type of opportunity only comes along once. Pinto da Costa wants to add a €60 million buyout clause along with an improved deal up to 2018.
"However, Jackson knows that increasing his buyout clause could make a move to the big-time next season a complex matter."
This would clearly make him almost unattainable for Premier League clubs, who shied away from Falcao and Edinson Cavani this summer at that sort of price, while Real Madrid are not likely to pay that amount after their world record outlay for Gareth Bale.
Porto have to balance their interests finely. If Martinez goes to and excels at the World Cup, his present clause will begin to look like a bargain, but they don't want to risk upsetting their star man before the season is out.
It does look like Porto and Martinez are accepting the striker will likely move on when a big bid arrives, the question is simply a case of how much.
Chelsea and Arsenal fans, would you be happy if you club bought Martinez?
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