Blackburn Rovers want Danny Sturridge included in Manchester City's offer for Roque Santa Cruz.

The Guardian says City may have to offer the striker Sturridge to Blackburn Rovers, or a fee of more than £18m, if they are to secure the signing of the Paraguayan forward Santa Cruz.

Sam Allardyce's principal objection to the sale of Santa Cruz is the limited time he would have to bring in a replacement.

Sunderland have rejected a bid for El Hadji Diouf, whom Allardyce managed at Bolton. City have offered Tal Ben Haim as part of a deal for Santa Cruz and are ready to release Nedum Onuoha, another defender, as an alternative. Allardyce, however, has his eye on Sturridge, 19, a high-class product of the City academy.

Sturridge, who scored against ­Blackburn last month, is in the final six months of his contract at City. His manager, Mark Hughes, said it was inexplicable that a player of Sturridge's potential should have been allowed to run his contract down. He is keen for him to agree a new deal. However, a deal involving Sturridge, either as a permanent transfer - which City would be reluctant to sanction - or on loan would be attractive to Blackburn.