Blues boss Steve Bruce tried to sign the England international midfielder during the January transfer window after Butt was told he could leave Old Trafford.
A move to Blues then failed to materialise and Butt decided to remain at Old Trafford although Bruce said then that he would be trying again to lure the player to St Andrew's during this close season.
Now Blackburn boss Graeme Souness has declared an interest in Butt who was today ruled out of Englands remaining games in the Euro 2004 Championships in Portugal after sustaining medial ligament damage during training.
Middlebrough, however, remain favourites for Butts signature should he decide to quit Old Trafford this summer.Have Your Say At The Messageboard