Manchester United moved three points clear at the top of the Premier League thanks to Cristiano Ronaldo's double.
Ronaldo has scored 26 goals in 51 games in 2007 for club and country
Christopher Samba came very close to giving Blackburn the lead when his rising shot crashed against the bar.
But Ronaldo's header and a side-footed finish, in the space of two first-half minutes, put United in total control.
And any hope Blackburn had of salvaging a point disappeared when David Dunn was sent off for picking up a second yellow card early in the second half.
Dunn's second booking was for a trip on Louis Saha and was possibly deserved, though his first booking, after he was adjudged to have fouled Carlos Tevez, looked a bit harsh.
However even before Dunn's dismissal Blackburn faced an uphill task after those two Ronaldo goals.
The year 2007 is turning out to be something of an annus mirabilis for Ronaldo, who has now scored a remarkable 26 goals for club and country in 51 games.
The Portuguese winger's double brought his season's tally to 10 and he came close to adding to it and claiming his first hat-trick for United when his quicksilver feet created the space for a long-range shot that went just over the bar.
And late on Ronaldo was denied by Brad Friedel, who also saved well from Rio Ferdinand.
Prior to Saturday Blackburn had recorded seven wins in eight games and initially Rovers more than matched United, with strikers Roque Santa Cruz and Benni McCarthy looking lively.
True, Blackburn had to survive some nervy moments and Friedel saved well from Carlos Tevez, while David Bentley had to clear a Ronaldo shot off the line.
Likewise Ryan Nelsen did well to block a Tevez shot, as did Morten Gamst Pedersen to charge down a Wes Brown effort.
But Blackburn had chances as well, notably when Samba's powerful shot cannoned off the crossbar.
Oops - Someone forgets how to spell David Bentley's name correctly
Enter Ronaldo, not for the first time in his career, to change the shape of the game.
He is not renowned for his heading ability, but the header he scored to give United the lead was a goal any centre forward would have been proud of.
Ryan Giggs swung over the corner from the left and Ronaldo's leap generated plenty of power for his goalward header.
Bentley was again on the line, though this time he was unable to rescue his side, only helping the ball into the roof of the net.
A minute later Blackburn's defence was unravelled by some impressive combination play involving Saha, Tevez and Ronaldo.
Saha flicked the ball to Tevez and the Argentine's superb cross - hit with the outside of his right foot - provided the space and time for Ronaldo to clip the ball past Friedel.
United keeper Edwin van der Sar had an altogether quieter time of it and he spent the second half as a virtual spectator until he had to get down quickly to save a Samba header.
After Dunn was sent off, Pedersen also briefly glimpsed goal, but the Norwegian blasted over.
In the closing minutes Ronaldo blotted his copybook when he was booked for a cynical push on Nelsen, a foul that left the New Zealander in a heap against the advertising hoardings.
Arsenal, who have played two games less than United, will return to the top if they beat Reading by two goals or more at the Madejski Stadium on Monday.
Man Utd: Van der Sar, Brown, Ferdinand, Vidic, Evra, Ronaldo, Anderson, Hargreaves (Carrick 77), Giggs, Tevez, Saha (Nani 68).
Subs Not Used: Kuszczak, O'Shea, Fletcher.
Goals: Ronaldo 34, 35.
Blackburn: Friedel, Emerton, Samba, Nelsen, Warnock, Bentley, Dunn, Mokoena, Pedersen, Santa Cruz (Derbyshire 78), McCarthy.
Subs Not Used: Brown, Ooijer, Kerimoglu, Berner.
Sent Off: Dunn (53).
Booked: Dunn, Mokoena, Nelsen, Samba.
Ref: Chris Foy (Merseyside).