Matthew Taylor sent the Foxes on their way with on own goal within the first six minutes, deflecting Paul Dickov's cross into his own net, and the game was up before half time as first Portsmouth target Muzzy Izzet struck the woodworkand Dickov combined with Marcus Bent to double their advantage.
A dire performance by Portsmouth improved in the second half as Lua-Lua and substitiute Ivica Mornar wasted good chances to drag themselves back into the match, before Nigel Quashie, of all people, drilled a left-footer past I"an Walker on 68 minutes.
Jamie Scowcroft ensured yet another win for Leicester over Pompey five minutes later with a scrappy goal the result of more poor defending, thus ending Portsmouth's recent good form.
Thankfully, judging by recent form, Portsmouth will not have to play them next season.