Chelsea's Diego Costa could reportedly return to Atletico Madrid in January in a deal that would see Jackson Martinez move in the opposite direction.
Neither striker has had a particularly impressive 2015-16 campaign to date, with Costa only scoring four times in 17 games for his English club this term.
The Spanish international is still regarded as a cult figure at Atletico, however, having helped the capital side win the La Liga title in the 2013-14 season.
Martinez, meanwhile, who joined Atletico from Porto in the summer, has only managed three goals for his new club.
According to Fichajes.com, a swap deal involving the two players has been discussed and both are said to be open to the possibility.
Costa is understood to have fallen out with Jose Mourinho in the latter stages of the Portuguese's second spell at Stamford Bridge.
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