Cardiff heaped further pressure on Blackburn manager Steve Kean as goals from Kenny Miller and Anthony Gerrard in a 2-0 victory put the Welsh club into the last four of the Carling Cup for the first time since 1966.
Scotland striker Miller opened the scoring in the 19th minute with a low left-footed finish and Gerrard sealed the win by nodding home five minutes after the break after Blackburn keeper Mark Bunn had failed to deal with a corner.
At the other end David Goodwillie had his headed effort well saved by Cardiff keeper Tom Heaton and Scott Dann also nodded wide, but in truth Rovers were well beaten and the visiting support made clear their dissatisfaction with repeated chants of "Kean out".
The evening had begun with Cardiff City Stadium uniting in a round of applause and a minute's silence in memory of Wales manager Gary Speed, with the home support regularly breaking into chants of "there's only one Gary Speed" throughout the contest.
Blackburn began to dominate and Heaton was forced into a sharp save as Grant Hanley hit the target with a header from a Morten Gamst Pedersen corner, but the Norwegian gifted the hosts the lead in the 19th minute.
Aron Gunnarsson seized on a poor pass by Pedersen to play Miller in to beat Bunn with a low left-footed finish.
Blackburn were showing signs of full-scale panic, best exemplified by Jason Lowe's booking for hauling down Craig Conway after being caught in possession.
David Dunn's drive from distance was tipped round the post by Heaton and a Dann header from the resulting corner was deflected over the bar as Blackburn rallied.
Cardiff had appeals for a penalty waved away early in the second half despite Mauro Formica making a clumsy challenge on Peter Whittingham on the edge of the box. But it only proved a brief reprieve for the visitors as Cardiff doubled their lead through Gerrard.
Bunn came for a Whittingham corner and got nowhere near it as Ben Turner headed back across goal for his defensive partner to finish.