By Phil McNulty
Blackburn eased to an impressive FA Cup fourth round victory at Luton.
Matt Derbyshire's fine 10th-minute strike put Blackburn on their way, and he then set up Benni McCarthy's simple tap-in nine minutes before half-time.
Derbyshire rose highest to head home Brett Emerton's cross after 56 minutes to add a deserved third for Blackburn.
Morten Gamst Pedersen got in on the act 16 minutes from time, rounding off a hugely-professional Blackburn display with a crisp left-foot volley.
Blackburn gave a debut to new £1.5m capture from Liverpool Stephen Warnock, and he was a key figure as they dominated the first 45 minutes.
It took Blackburn only 10 minutes to take the lead when the highly-promising Derbyshire sent a fine right-foot finish across Marlon Beresford from McCarthy's pass.
606: DEBATE
Luton suffered a blow nine minutes later when captain Chris Coyne hobbled off after sustaining an injury attempting to block Warnock.
And their troubles increased after 36 minutes when Derbyshire headed Pedersen's cross into the path of McCarthy, who applied a simple finish.
The game was effectively over as a contest 11 minutes after the break, Derbyshire rising well to head Emerton's cross beyond Beresford.
Blackburn - missing broken leg victim Robbie Savage - were so comfortable they were able to introduce new defensive signing Christopher Samba, replacing returning captain Ryan Nelsen.
And they confirmed their huge superiority with a fourth goal 16 minutes from time, Pedersen expertly volleying into the bottom corner.
Blackburn manager Mark Hughes on Matt Derbyshire:
"I've got options up front but when a young player makes an impact by scoring goals then you have to play him."
"We sent him out to Wrexham on loan and he did well and scored plenty of goals, so we thought he could make the step-up to at least Championship level.
"Maybe the step-up has come sooner than we expected but he's taken his chance."
Luton manager Mike Newell:
"Their extra quality showed but I half expected it with the way they've been playing and the disruption we've had.
"It's not only about losing Rowan Vine and Carlos Edwards. If you look at our injury list we're missing half a team."
Newell also praised Blackburn's two-goal Matt Derbyshire.
"He will get better. He's got pace and scores goals. What more can you ask from a striker?"
Luton: Beresford, Foley, Davis, Coyne (Keane 21), Perrett, Robinson, Emanuel, Langley, Bell (Morgan 58), Boyd, Talbot (O'Leary 82).
Subs Not Used: Brill, Spring.
Blackburn: Friedel, Khizanishvili (Gallagher 76), Nelsen (Samba 70), Henchoz, Warnock, Emerton, Mokoena, Bentley, Pedersen, Derbyshire, McCarthy (Jeffers 67).
Subs Not Used: Enckelman, Nonda.
Booked: Khizanishvili.
Goals: Derbyshire 10, McCarthy 37, Derbyshire 56, Pedersen 74.
Att: 5,887
Ref: S Bennett (Kent).