Lomana LuaLua needed just 25 minutes to inspire Portsmouth to a devastating victory over Southampton which pushed their rivals closer relegation from the Barclays Premiership.

LuaLua struck twice and launched a series of attacks as Pompey swept aside Saints in a stunning opening at Fratton Park.

He went off injured after scoring his second, but the damage was already done for Saints and their former Pompey manager Harry Redknapp.

LuaLua was brought down in the opening 90 seconds for a penalty - which Aiyegbeni Yakubu stylishly converted - and then saw captain Arjan de Zeeuw head in a Patrik Berger free-kick.

Henri Camara thought he had got Saints going with a smart, solo effort on 20 minutes. But then LuaLua, a man on fire, struck two in five minutes as Southampton's defence fell apart for the second weekend in succession.

Aside from their perilous situation at the bottom of Premiership, Saints suffered major problems even before the start when key striker Peter Crouch was injured in the warm-up. He was forced to pull out and was replaced by Camara.

It was Crouch's last-gasp penalty which won the FA Cup clash between the two clubs at St Mary's in February - and after his 14 goals in total this season, his loss was a major blow.

It was another spot-kick which was to bring this game into life. But it went to Pompey, and Southampton never recovered.

Their Finland goalkeeper Antti Niemi came charging from his goal as LuaLua chased a Gary O'Neil through pass into the area - and the Scandinavian took out the Congo striker in no uncertain fashion.

LuaLua stayed down for a while but eventually recovered to see strike partner Yakubu coolly chip his 16th goal of the season into the roof of the net to open the scoring.

The surprise initially, though, was that referee Steve Dunn did not even book Niemi for the foul when a red card looked possible - although TV replays later suggested LuaLua's run was taking him away from goal.

Pompey could have had a second on eight minutes as they pushed home their early advantage. Patrik Berger, back in the starting line-up after two games on the bench, swung in a cross from the right - and defender Dejan Stefanovic was up to connect but sent the ball flashing over the bar.

LuaLua was nonetheless virtually unstoppable.

After he chipped in outrageously from the left and made Niemi launch himself to tip the ball over the bar in the 11th minute, almost knocking himself out on an upright, the flying striker continued to torment the visitors.

Saints found some relief in a spate of raids. But de Zeeuw was forever in their way, and it was also his powerful header which put Pompey two goals to the good in the 17th minute - just as stewards were removing a group of Southampton fans from behind the goal.

Berger arrowed in a free-kick, and the big Dutchman was criminally unmarked as he thundered through a crowd of players to head home.

Within two minutes, Saints fans finally had something to cheer when Camara sped past Matt Taylor and Stefanovic to beat Jamie Ashdown with an unstoppable shot for 2-1.

But their joy did not last long as Pompey regained their two-goal cushion with an almost comical goal in the 22nd minute.

Saints were attacking when a sudden long ball by Berger saw LuaLua chasing from half-way - and despite at least two markers in position, Niemi came from his line and outside the box to try to intercept the loose ball.

Instead, LuaLua was on to it like a flash and scooped a wonderful effort into the empty net to bring the breathless home fans to their feet yet again.

Four minutes later, the somersaulting striker was at it again - with an explosive finish after Yakubu tried to pass the ball inside instead of shooting. LuaLua's effort flew in off a post from almost 25 yards.

Niemi made up for earlier blunders with a fine save from Berger and then another to deny LuaLua a hat-trick - and even though the former Newcastle striker went off soon afterwards and Kevin Phillips was unlucky to finish off the mark with a header, substitute Diomansy Kamara and Berger should have added more Pompey goals before the break.

Kamara had two more chances after the break, while Yakubu was also let down by a poor first touch with the goal gaping in front of him.

Largely the winners were happy to play keep-ball, with midfielders Richard Hughes and Steve Stone non-stop battlers for the ball.

Saints' finishing was even worse - and despite a switch to 3-5-2 for the second half they could make no impression.

Teams

Portsmouth Ashdown, Griffin, Stefanovic, De Zeeuw, Taylor, Stone, O'Neil, Hughes, Berger (Cisse 57), Yakubu (Skopelitis 78), LuaLua (Kamara 28).

Subs Not Used: Fuller, Hislop.

Booked: Hughes, Griffin.

Goals: Yakubu 4 pen, De Zeeuw 17, LuaLua 22, 27.

Southampton Niemi, Delap, Lundekvam, Jakobsson, Higginbotham, Telfer, Oakley (Bernard 45), Redknapp, Quashie, Phillips, Camara.

Subs Not Used: Anders Svensson, Davenport, Nilsson, Smith.

Booked: Lundekvam, Redknapp.

Goals: Camara 20.

Att: 20,210

Ref: S Dunn (Gloucestershire).