It was a contest already filled with fire and fury, with Harry Redknapp and Jim Smith making their much-anticipated return to Fratton Park following their departure in November 2004.
It also saw the Blues’ Division One title winner Nigel Quashie start for the Saints just months after the midfielder swapped PO4 for St Mary’s in the January transfer window.
With a capacity crowd at Fratton Park, Alain Perrin’s men got off to the best start when Yakubu netted from the spot after just four minutes. The lead was then doubled by captain Arjan De Zeeuw, who headed home Patrik Berger’s 17th-minute free kick.
Although Henri Camara got a goal back, a spectacular double from Lomana LuaLua sealed the dominant 4-1 victory, while also confirming Pompey’s top flight status.
Meanwhile, Southampton would go onto finish the season in the bottom three, with West Brom beating the Blues on the final day to help relegate their bitter rivals.
With the demolition derby now 20 years old and with the prospect of another two meetings between the two sides, we’ve delved into the archives to find the best photos from the 4-1 triumph.
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1. Pompey 4-1 Southampton: 20 years on
Lomana LuaLua does his iconic backflip as the Fratton faithful celebrate in the background. | EMPICS Sport
2. Pompey 4-1 Southampton: 20 years on
'Harry and Jim' the Fratton End used to sing. But the duo were in the away dugout for the first time since their Pompey exit in November 2004. | Getty Images
3. Pompey 4-1 Southampton: 20 years on
LuaLua was clattered down in the box by Antii Niemi within the opening minutes at PO4. | JONATHAN BRADY
4. Pompey 4-1 Southampton: 20 years on
Yakubu opened the scoring for Pompey from the spot after just four minutes. | Getty Images