Blackburn warmed up for next weekend's FA Cup semi-final with an emphatic victory that should secure their Premiership survival for this season.

With six matches remaining, manager Mark Hughes' side are now nine points clear of the relegation zone and only a critical case of the jitters over the closing five weeks will surely see them flirt again with the bottom three.

But as for Harry Redknapp's Saints, all their good work in their previous away game at Middlesbrough, where they ran out 3-1 winners, was undone with a catastrophic 90 minutes at Ewood Park.

With Crystal Palace and West Brom, the two teams directly below them, playing tomorrow at Everton and Aston Villa respectively, there is every chance Southampton will be back in the bottom three.

Alarmingly for Redknapp, Rovers were just too strong in all areas, although they were lifted by taking an

11th-minute lead through Morten Gamst Pedersen.

It was a goal of outstanding quality, which was in stark contrast to the inauspicious start that had preceded the Norwegian's seventh goal of the season.

In truth, Pedersen could not have asked for any more from Aaron Mokoena who delivered a cross-field, 60-yard ball from inside his own half into the stride of the left winger.

Given the pace and weight on the pass, covering defender Rory Delap had no chance of matching the run of Pedersen, who had stolen round the back of the Saints right-back.

Pedersen then took one touch which set him up for a crashing left-foot, angled drive underneath Paul Smith, standing in for Antti Niemi who was a late withdrawal with a hip injury.

Nine minutes later and Southampton came within a whisker of the equaliser with what proved to be their first chance of the half, and their best of the game.

Nigel Quashie's corner from the right was low and poorly struck, but it found its way into the area where Henri Camara struck a first-time shot that shaved the right-hand post.

Within seconds Rovers countered with David Thompson delivering from the right, only for a fast-arriving Pedersen to find air in his attempt to smash the ball into the net, all in stark contrast to his previous outstanding strike.

With Hughes' side pressing and in control, they again came close to adding a second in the 25th minute, but Garry Flitcroft's far-post cross from the left just evaded the head of the leaping Steven Reid.

It was then Smith who spared his side a two-goal deficit, producing a reaction save to a flicked near-post header from a fit-again Paul Dickov - back after three weeks out with a groin injury - steering the ball away from underneath his own crossbar.

At least Southampton finished the half strongly, although Peter Crouch's long-distance shot-on-the-turn was comfortably gathered by Brad Friedel who enjoyed a quiet afternoon.

Crouch followed that in injury time by steering a header just wide from a Graeme Le Saux left-wing free-kick, albeit with Friedel watching it go by.

That proved to be the last time Le Saux figured in the game as he was withdrawn at the break and replaced by Kevin Phillips as Redknapp adopted a more-attacking line-up for the second period.

Little was he to know his plans would be unravelled by two goals inside the opening 10 minutes after the

restart.

The first was down to sheer bad luck, although Reid was allowed too much room on the right wing to receive a through ball from Lucas Neill before driving in a low cross that a sliding Andreas Jakobsson squeezed home at the near post past his own keeper.

The game-killing third was down to sloppy defending as Dominic Matteo was first allowed to square a pass to Reid from inside the area after latching on to a low Pedersen corner.

How Reid was left unmarked from 10 yards out will be one of the searching questions Redknapp will ask of his players as the midfielder picked his spot to seal the points for his first goal since late November, and only second of the season.

Friedel remained untested until six minutes from time when palming away an angled Phillips drive, with that chance as close as Southampton came to pulling one back.

Redknapp and his players will now anxiously watch tomorrow's games involving Palace and the Baggies, praying for the results to go their way.

Blackburn can now prepare for their showdown with Arsenal at Cardiff's Millennium Stadium next Saturday feeling safe in the knowledge they should be playing Premiership football again next season.

Teams:

Blackburn Friedel, Neill, Todd, Nelsen, Matteo, Mokoena, Thompson (Emerton 45), Reid (Stead 74), Flitcroft (Tugay 49), Pedersen, Dickov.

Subs Not Used: Amoruso, Enckelman.

Booked: Emerton, Reid.

Goals: Pedersen 11, Jakobsson 48 og, Reid 55.

Southampton Smith, Delap, Lundekvam, Jakobsson, Bernard (Higginbotham 83), Telfer, Redknapp, Quashie, Le Saux (Phillips 45), Crouch, Camara (Anders Svensson 75).

Subs Not Used: Poke, Davenport.

Booked: Camara.

Att: 20,726

Ref: N Barry (N Lincolnshire).