Much of the build-up surrounded two men involved in high-profile incidents, with this match the first time former Saints boss Alan Pardew has been allowed into a stadium, albeit banned from the touchline, since head-butting Hull's David Meyler.
There was also scrutiny on referee Andre Marriner as he returned to action just a week after his embarrassing gaffe in Chelsea's win against Arsenal, although the main talking point after a fine 4-0 win for Saints was the display of their World Cup hopefuls.
Mauricio Pochettino's side created 14 chances in the first half alone, although it took until stoppage time in the first period for Jay Rodriguez to eventually find a way past the inspired Rob Elliot, making his first league start of the season.
Rickie Lambert unselfishly provided the assist for the opener and had one of his own soon four minutes into the second half, before Adam Lallana rifled home an outstanding 25-yard strike to put Saints out of sight.
The Saints captain appeared to be growing frustrated with Marriner's apparent attempt to avoid dishing out cards, with the referee only brandishing a yellow to Massadio Haidara with 14 minutes remaining.
The referee's display will no doubt be closely examined after a match which Saints managed to extra gloss through Rodriguez's fifth goal in four matches.
Victory looked likely from the outset and the home fans thought they had a goal to celebrate after eight minutes, only for it become clear Rodriguez's strike had hit the side netting.
The England forward powered a header just wide soon after, before Elliot prevented him directing home a Lambert cross with a fine save.
The Newcastle goalkeeper was getting no respite from his defence and produced a fine reaction save when Lambert went through one-on-one in the 16th minute and denied the England striker again soon after.
Lallana wasted a glorious chance by directing a looped Calum Chambers' header wide from close range as Saints continued to threaten.
Newcastle began to settle but, aside from a hopeful Yoan Gouffran prod goalwards, were creating little and looking shaky at the back.
Elliot had to pull off another incredible save to deny a close-range Rodriguez header before he finally found a way past the inspired Magpies keeper.
Lambert beat the offside trap to latch onto a Steven Davis ball over the top, bearing down on goal and squaring to the unmarked Rodriguez, whose effort may have been scuffed but finally beat Elliot.
Pardew will have no doubt given his players a dressing down at half-time and took off the ineffective Mapou Yanga-Mbiwa and Hatem Ben Arfa.
The introduction of Davide Santon and Luuk de Jong did little to stem the tide, though, with Haidara forced to head clear of danger shortly after the restart. It was not long until Southampton doubled their advantage, with Lallana cutting back and clipping over a fine ball to Lambert, who again beat the offside trap and stabbed past Elliot at his near post.
Moussa Sissoko flashed strike across the face of goal as he tried to give the 2,187 away fans to shout about, before Papiss Cisse somehow avoided retribution for a late challenge on Chambers.
Luke Shaw also hit the deck under after a Sissoko challenge but it was not until the 76th minute that Marriner finally dished out a card, giving Haidara a booking for a late challenge on James Ward-Prowse.
By that point, the match had been put to bed by a moment of magic from Lallana. Collecting the ball deep in the visitors' half, he pushed on and unleashed a wonderful 25-yard strike past Elliot.
Saints continued to press and the goalkeeper produced another wonderful save to tip over a Ward-Prowse follow-up strike after Rodriguez had hit the woodwork.
A wonderful Shaw block denied Gouffran grabbing a late consolation at the end of a match that got worse for the visitors when Rodriguez cut back and fired through Elliot's legs with a minute remaining.