Birmingham could lose out in their bid to sign Walter Pandiani after Deportivo La Coruna accepted a £2.7m (€4.05m) bid from Real Zaragoza for the Uruguayan striker.
Blues have so far only been prepared to offer around £1.7m (€2.5m) for the 29-year-old striker who spent the second half of last season on loan at St Andrews.
Pandiani, who scored four goals in 13 games for City, has constantly stated his desire to complete a permanent switch to Birmingham.
But his agent Francis Martin admitted the agreement between Deportivo and Zaragoza for former dustman Pandiani could put the move to Birmingham in doubt.
Martin said: “The offer (from Zaragoza) has thrown a spanner in the works. Birmingham were holding out for as long as possible and waiting for Deportivo to panic and accept their offer.
“If Zaragoza had not come in, they could have probably held on until the end of August. But now it’s a case of giving Birmingham as long as possible to have a bid accepted by upping their offer.
“Walter will also want to think about things – which will give Birmingham more time – but it’s whether they want to pay that much, with wages on top, for a player approaching 30.
“But it’s also up to the lad whether he wants to reject the move and wait for Birmingham to increase their bid and give him his ideal move.”
Birmingham manager Steve Bruce has admitted the two clubs “are miles apart” regarding agreeing a fee for Pandiani, know as 'The Rifle'.
His need to sign the player has lessened after obtaining the signature of his number one striker target Mikael Forssell who has joined City in a switch from Chelsea.