Steve Coppell has admitted Reading's chances of signing Ghana defender John Mensah are fading.
The Royals boss had been hoping to bring the 23-year-old to The Madejski Stadium for a club record fee of £3.5 million.
Coppell is still keen on the Rennes star, who impressed for The Black Stars during the World Cup, but is less optimistic.
"We are not in a position to start the ball rolling," he explained.
"We depend on others and are waiting for the fall-out on other deals."
However, Reading's cause could be helped by Rennes' capture of Mario Melchiot on a free transfer this week.
The Premiership new boys are continuing to look at other options, and have handed Lokomotiv Moscow defender Andre Stephane Bikey a trial.
The Cameroonian has been invited on Reading's pre-season tour to Sweden, and could even play in Thursday's friendly against Gallstad if he impresses Coppell in training.
"Bikey is just one of many centre backs we are looking at and, depending on what shape he is in, he could play," Coppell told the Reading Evening Post.
"To be honest, we have gone down a few blind alleys concerning possible transfers in recent days and we have suffered a couple of knock-backs at the ninth or 10th hour."