Sport says Barca could move to sign Koke in the coming days and immediately loan him back to Atletico.
Barca are scrambling after their transfer ban - to begin in January 16 - was upheld by FIFA upon appeal yesterday.
They're now weighing up a move for Koke to secure him now, rather than risk losing the youngster to a rival next year.
Koke penned terms to 2019 with Atletico earlier this summer.
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