Oguchi Onyewu is believed to have agreed a deal with Fenerbahce after Birmingham stalled over a move.
The America international is currently with his country as they play in the Confederations Cup in South Africa.
His representatives have been locked in talks with Birmingham over the past few weeks as the Blues looked to have held off the likes of Fulham and Wolves to land the 27-year-old.
Onyewu is available on a free transfer as his contract at Standard Liege is due to expire this month.
While Standard have offered him fresh terms, Onyewu has decided to quit Belgium.
He was looking to move to England, but the deal with Birmingham has failed to materialise as expected.
Now it is understood a three-year deal has been agreed with Istanbul giants Fenerbahce.
Meanwhile, reports in France suggest Birmingham could have turned their attentions to Mauro Cetto.
The Argentine defender is currently at Toulouse and is very highly-rated there, captaining the Pink City outfit last term.
It is claimed Birmingham made an enquiry about the 27-year-old, but were given a short-shrift response from Toulouse.