The Palace boss yesterday said: "Darren's a valued squad member. He's still our player and it's up to him to get back in the side."
However Reading are homing in on the 6ft 3inch centre-back who will provide competition for the eternally injured Adie Williams and Steve Brown.
The Royals revealed they had agreed a fee with the Eagles for Powell a little over a week ago but the player has been recuperating from a hamstring injury so consequently has been unable to complete the move thus far.
But tomorrow is D-Day as far as the transfer is concerned with the player scheduled for a Madejski medical.
Director of Football Nicky Hammond confirmed that the drawn-out transfer is nearing completion. "We're hopeful of concluding the transfer early next week," he bluntly remarked to the official site.
Powell previously played under Coppell at Brentford but he left the Bees in the summer of 2002 for Crystal Palace, just as the now Reading manager left Griffin Park following their bungled promotion campaign.