Matt Derbyshire's rise to prominence continued as Blackburn ruthlessly swept aside Luton to move into the FA Cup fifth round.

The 20-year-old scored either side of the break to take his tally to five goals in his last six appearances while Benni McCarthy and Morten Gamst Pedersen also found the net.

Derbyshire, a lifelong Blackburn fan who initially worked as a coach in the club's community office before signing as a player in a £20,000 move from Great Harwood, this week agreed a new contract that will keep him at Ewood Park until 2010.

And he celebrated his new deal in style as Rovers recorded a crushing victory which did not flatter them.

Luton boss Mike Newell, who helped Blackburn win the Premiership title under Kenny Dalglish in 1995, has now only a grim relegation battle to look forward to.

But for Rovers counterpart Mark Hughes, there are increasingly heady days and this latest success took him one step towards a return to Wembley.

The former Wales striker lifted the FA Cup as a Manchester United player in 1985, 1990 and 1994 before claiming his fourth winners' medal with Chelsea in 1997.

With new signing Stephen Warnock enjoying a hugely impressive debut at left-back and Ryan Nelsen also making his first appearance since last April, Blackburn disposed of Luton with ease.

Newell handed new signing Drew Talbot his debut up front following his arrival from Sheffield Wednesday.

However, Croatian midfielder Ahmet Brkovic missed out after injuring is ankle following a horrific tackle from QPR midfielder Stefan Bailey during the Hatters' third-round replay victory in midweek.

Rovers debutant Warnock, who lined up at left-back, caught the eye in the fifth minute when he showed impressive pace and skill to carry the ball forward and send Brett Emerton racing clear.

The Australia international forced a corner which was delivered by Pedersen to the far post.

No Rovers players was on hand to profit but Hughes' men were rewarded for their early dominance when Derbyshire produced a fine goal to open the scoring in the 10th minute.

When McCarthy slipped a hopeful looking pass into his path, there appeared to be little danger when Derbyshire collected possession on the right-hand side of Luton's 18-yard box.

However, he calmly took a touch before rifling a rising shot which flew past Marlon Beresford and into the top corner.

Yet Luton's response was impressive and they quickly sought to force their way back into the game.

When Sol Davis launched a long punt deep into Rovers territory in the 18th minute, Blackburn goalkeeper Brad Friedel punched weakly and the ball fell to David Bell 30 yards from goal.

Friedel was some way off his line but Bell could not control his attempted lob and the ball sailed harmlessly over the crossbar.

Luton's best chance of the half came in the 34th minute when Lewis Emanuel swung in a dangerous corner from the right and Talbot rose unmarked to send the ball goalwards.

He failed to make solid contact but his flick still found it was to Richard Langley, who failed to divert the ball past Friedel from just two yards.

Three minutes later, Blackburn all but secured their passage into the fifth round when a delightful move sent them 2-0 ahead.

Warnock was again heavily involved, embarking on a strong run down the left flank before slipping a neat pass on to Pedersen.

The Norwegian sent over a dangerous cross which Derbyshire bravely headed across the face of goal to give McCarthy an easy tap-in from inside the six-yard box.

McCarthy wheeled away in celebration of his 15th goal of an increasingly productive season, while Derbyshire recieved treatment after taking a boot in the face as reward for his bravery.

Blackburn extended their advantage 11 minutes after the restart when Emerton swung in a teasing cross which Derbyshire rose to dispatch with a firm header past Beresford to put the tie beyond doubt.

Luton attempted to hit back but Rovers' experienced central defensive duo, Stephane Henchoz and Nelsen, refused to budge.

Hughes then replaced McCarthy with former Everton and Arsenal striker Francis Jeffers in the 67th minute, and then withdrew Nelsen and brought on Christopher Samba.

Blackburn refused to ease up and Pedersen claimed his seventh goal of the season in the 74th minute to put the seal on an emphatic victory.

A deep cross from the right flank found Pedersen unmarked at the far post, and he smashed a left-foot half-volley past Beresford and into the corner to seal a solid win.

Teams:

Luton (0) 0 Blackburn (2) 4

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).