Toon turned to the Senegal international after failing to find agreement with Lyon over a fee for Bafetimbi Gomis.
A bid of €12 million was made by Newcastle, says Fanatik, but it fell short of Fener's €17 million valuation.
Sow was counting on Newcastle returning with an improved offer, confessing to Fener fans on Twitter: "I don't know what is happening. But I love Fenerbahce."
However, that second bid never arrived.
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